This page lists 39 first aid words starting with C, ranging from “Cardiac Arrest” to “Cyanosis.” The terms cover injuries, emergency conditions, assessment techniques, and life-saving procedures used in first aid. They give you the vocabulary to act quickly, communicate clearly, and handle emergencies with more confidence.
First aid words are the standard terms used to describe injuries, symptoms, and the actions taken before professional help arrives. Structured first aid vocabulary was first formalized in the 1870s through military field medicine and organizations like St. John Ambulance. Today these words appear in training courses, workplace safety programs, and emergency services around the world.
Below you’ll find the table with Word, Definition, and Description.
Word: The specific first aid term, listed alphabetically, so you can scan and find what you need at a glance.
Definition: A plain-language explanation of what each term means, giving you a clear and accurate understanding of the concept.
Description: Practical context showing how each term applies in a real emergency, including what first aid actions or precautions typically apply.
First aid words
| Word | Definition |
|---|---|
| Cardiac Arrest | The sudden cessation of the heart’s pumping function, stopping blood circulation to the brain and body |
| Cardiopulmonary Resuscitation | An emergency procedure combining chest compressions and rescue breaths to maintain circulation when the heart has stopped |
| Capillary Refill | The time it takes for color to return to a nail bed or fingertip after brief pressure is applied and released |
| Carbon Monoxide Poisoning | A condition caused by inhaling carbon monoxide gas, which displaces oxygen in the blood |
| Carotid Pulse | The pulse felt in the carotid artery on either side of the neck, used to confirm heart activity |
| Casualty | A person who has been injured, taken ill, or incapacitated in an accident or emergency situation |
| Casualty Assessment | The systematic process of evaluating an injured or ill person to identify life-threatening conditions |
| Cervical Collar | A rigid or semi-rigid neck brace used to immobilize the cervical spine after suspected neck or spinal injury |
| Cervical Spine | The uppermost section of the vertebral column consisting of seven vertebrae located in the neck |
| Chain of Survival | A sequence of critical actions that, performed in order, maximize survival rates during cardiac emergencies |
| Chemical Burn | Damage to the skin or eyes caused by contact with a corrosive or caustic chemical substance |
| Chest Compression | The act of pressing rhythmically on the sternum during CPR to simulate the heart’s pumping action |
| Chest Pain | Discomfort, pressure, or pain in the chest that may signal a heart attack or other cardiac emergency |
| Chilblain | A skin condition caused by repeated exposure to cold and damp conditions, resulting in redness, itching, and swelling |
| Choking | Partial or complete obstruction of the airway by a foreign object, preventing normal breathing |
| Circulation | The continuous movement of blood through the heart and body, delivering oxygen and nutrients to tissues |
| Clinical Death | The cessation of heartbeat and breathing, representing the onset of the resuscitation window |
| Clotting | The physiological process by which blood solidifies to form a clot and stop bleeding at a wound site |
| Closed Fracture | A bone break in which the skin remains intact and the bone does not penetrate the skin surface |
| Coagulation | The biochemical process by which blood transitions from a liquid to a gel-like state to prevent blood loss |
| Cold Compress | A cloth or pack chilled with ice or cold water applied to an injury to reduce swelling and relieve pain |
| Collar and Cuff | A simple sling made from cloth that supports the forearm and wrist by looping around the neck |
| Coma | A state of deep, prolonged unconsciousness in which the person cannot be awakened and does not respond to stimuli |
| Compression | The application of firm, steady pressure to a wound or injured area to control bleeding or reduce swelling |
| Concussion | A mild traumatic brain injury caused by a blow or jolt to the head that temporarily disrupts normal brain function |
| Consciousness | The state of being awake, alert, and aware of one’s surroundings and internal state |
| Contaminant | Any foreign substance introduced into a wound that increases the risk of infection or complications |
| Contusion | A bruise caused by blunt trauma that damages blood vessels under the skin without breaking the surface |
| Controlled Breathing | A deliberate technique of regulating the breath to manage pain, anxiety, or hyperventilation |
| Convulsion | A sudden episode of involuntary, uncontrolled muscle contractions caused by abnormal electrical activity in the brain |
| CPR | Abbreviation for Cardiopulmonary Resuscitation; an emergency life-saving technique combining chest compressions and rescue breaths |
| Cradle Carry | A technique for moving an injured person by supporting them horizontally under the knees and across the upper back |
| Cramp | A sudden, painful, involuntary contraction of a muscle that causes temporary loss of function in that area |
| Crepitus | A crackling or grating sensation or sound produced when fractured bone ends move and rub against each other |
| Croup | A childhood respiratory illness causing inflammation of the upper airway and a characteristic barking cough |
| Crush Injury | Tissue damage resulting from a high degree of force or prolonged compression applied to part of the body |
| Crush Syndrome | A systemic condition triggered by the release of muscle breakdown products into the bloodstream when prolonged compression is relieved |
| Cut | A laceration or incision through the skin caused by a sharp object or blunt trauma |
| Cyanosis | A bluish discoloration of the skin, lips, or fingernails resulting from insufficient oxygen in the blood |
Descriptions
Cardiac Arrest
Cardiac arrest is a life-threatening emergency requiring immediate CPR and defibrillation. Without treatment within minutes, permanent brain damage or death can occur.
Cardiopulmonary Resuscitation
CPR keeps oxygenated blood flowing to the brain and vital organs during cardiac arrest. It should be started immediately and continued until emergency medical services arrive.
Capillary Refill
Capillary refill time is a quick check for circulation quality. A refill time greater than two seconds may indicate poor circulation or shock and warrants urgent medical evaluation.
Carbon Monoxide Poisoning
Carbon monoxide poisoning symptoms include headache, dizziness, and confusion. First aid involves moving the person to fresh air immediately and calling emergency services.
Carotid Pulse
The carotid pulse is checked in unresponsive adults to determine if the heart is beating. If no pulse is detected, CPR should be started immediately while emergency services are called.
Casualty
In first aid, a casualty is anyone requiring emergency care. Assessment follows structured protocols such as DR ABC: Danger, Response, Airway, Breathing, and Circulation.
Casualty Assessment
Casualty assessment includes checking responsiveness, airway, breathing, and circulation, and identifying injuries requiring immediate treatment before detailed examination continues.
Cervical Collar
A cervical collar is applied when spinal injury is suspected to prevent further damage. It holds the head and neck in a neutral position until professional medical care is available.
Cervical Spine
Protecting the cervical spine is critical when head, neck, or back injury is suspected. The head and neck must be manually stabilized to prevent worsening a potential spinal cord injury.
Chain of Survival
The chain of survival includes early recognition of the emergency, calling for help, early CPR, early defibrillation, and post-resuscitation care. Each link is essential to improving outcomes.
Chemical Burn
Chemical burns require removing contaminated clothing and flushing the affected area with large amounts of clean water for at least 20 minutes, followed by immediate medical attention.
Chest Compression
Chest compressions are performed at a depth of about 2 inches at a rate of 100–120 per minute. They are the most critical component of CPR for maintaining blood circulation during cardiac arrest.
Chest Pain
Chest pain should never be ignored. First aid involves calling emergency services, resting the person in a comfortable position, and giving aspirin if available and not contraindicated.
Chilblain
Chilblains affect fingers, toes, and ears. First aid involves gently warming the area, avoiding rubbing, and protecting the skin from further cold exposure to prevent tissue damage.
Choking
Choking is treated with back blows and abdominal thrusts. Complete airway obstruction is a medical emergency that can be fatal within minutes if not promptly relieved.
Circulation
Assessing circulation involves checking for a pulse and signs of adequate blood flow. Absent or poor circulation indicates the need for CPR or urgent treatment for circulatory shock.
Clinical Death
Clinical death is distinguishable from biological death because timely CPR and defibrillation may restore vital functions. Acting immediately during clinical death dramatically improves survival chances.
Clotting
Clotting is triggered by a cascade of chemical reactions at the injury site. In first aid, applying direct firm pressure to a wound supports and accelerates the body’s natural clotting mechanism.
Closed Fracture
Closed fractures are managed by immobilizing the injured area, applying a cold pack to reduce swelling, and transporting the person to medical care without moving the limb unnecessarily.
Coagulation
Coagulation is the body’s primary defense against excessive bleeding. First aiders support coagulation by applying firm direct pressure to wounds to help the clot form and hold.
Cold Compress
Cold compresses constrict blood vessels and reduce inflammation, making them effective for sprains, bruises, and muscle injuries. They should be applied for 15–20 minutes at a time.
Collar and Cuff
A collar and cuff is used for arm and shoulder injuries such as fractures and dislocations. It supports the weight of the arm and limits movement to reduce pain and prevent further injury.
Coma
A comatose person who is breathing should be placed in the recovery position to protect the airway. Calling emergency services immediately while monitoring breathing is essential.
Compression
Compression is a cornerstone of wound management and the RICE protocol. Sustained pressure on a wound slows blood loss and supports the body’s natural clotting process.
Concussion
Concussion symptoms include headache, confusion, dizziness, and nausea. First aid involves rest, monitoring for worsening symptoms, and prompt medical evaluation to rule out serious injury.
Consciousness
Assessing consciousness is the first step in evaluating a casualty. The AVPU scale (Alert, Voice, Pain, Unresponsive) is a quick first aid tool for gauging a person’s level of awareness.
Contaminant
Minimizing wound contamination is critical in first aid. Wounds should be rinsed with clean running water and covered with sterile dressings to reduce the risk of infection and delayed healing.
Contusion
Contusions are managed using the RICE method: Rest, Ice, Compression, and Elevation. While they usually resolve on their own, severe contusions may indicate underlying muscle or organ damage.
Controlled Breathing
Controlled breathing uses slow, deep inhalations and exhalations to calm the nervous system. It is used to help a panicking or hyperventilating person restore a normal respiratory rhythm.
Convulsion
During a convulsion, bystanders should clear the area of hazards and never restrain the person. After the seizure ends, placing them in the recovery position helps protect their airway.
CPR
CPR can double or triple survival rates after cardiac arrest. Hands-only CPR (compressions alone) is effective and widely recommended for untrained bystanders.
Cradle Carry
The cradle carry is used to transport casualties who cannot walk. It suits shorter distances and requires the rescuer to bear the person’s full body weight throughout the move.
Cramp
Muscle cramps are relieved by gently stretching and massaging the affected muscle. They are commonly caused by dehydration, overexertion, heat, or electrolyte imbalances.
Crepitus
Crepitus signals a likely fracture and means the injured area must be immobilized immediately. Moving the affected limb risks worsening the fracture and causing additional tissue damage.
Croup
Croup can cause significant breathing difficulty in young children. First aid involves keeping the child calm and upright, and seeking urgent medical attention if breathing is severely affected.
Crush Injury
Crush injuries can damage muscles, nerves, and blood vessels and may lead to life-threatening systemic complications. Emergency services should be called immediately for any significant crush injury.
Crush Syndrome
When a crush victim is freed, myoglobin from damaged muscle can overwhelm the kidneys and cause acute kidney failure. Early intravenous fluids administered by paramedics are the primary treatment.
Cut
Cuts are treated by cleaning the wound with clean water, applying direct pressure to control bleeding, and covering with a sterile dressing. Deep or gaping cuts may require stitches and medical evaluation.
Cyanosis
Cyanosis is a sign of dangerously low blood oxygen levels and is a medical emergency. It may indicate respiratory failure, cardiac arrest, or severe airway obstruction requiring immediate intervention.