Here you’ll find 36 Personality traits that start with O, organized from “Obedient” to “Oversensitive”. They cover social, emotional, and cognitive descriptors commonly used in psychology, writing, and self-help. Use this list for character development, classroom activities, or quick reference during research and reflection.
Personality traits that start with O are single-word or hyphenated descriptors of habitual thoughts, feelings, and behaviors. For example, “optimistic” gained wider use in positive psychology and everyday language during the late 20th century.
Below you’ll find the table with Trait, Definition, Context, and Related traits.
Trait: Lists the single-word personality term so you can quickly scan and choose the exact word you need.
Definition: Gives a concise meaning and distinguishing features so you can understand the trait’s typical behavior or mindset.
Context: Notes common situations, roles, or fields where the trait appears, helping you apply it to real examples.
Related traits: Lists synonyms, opposites, or nearby descriptors so you can compare options and refine your word choices.
Personality traits that start with O
| Trait | Part of speech | Model/Source | Synonyms |
|---|---|---|---|
| Openness | noun | Big Five | curiosity; creativity; imagination |
| Open-minded | adjective | common usage | receptive; tolerant; unbiased |
| Outgoing | adjective | Big Five (Extraversion) | sociable; gregarious; friendly |
| Outspoken | adjective | common usage | forthright; candid; blunt |
| Optimistic | adjective | common usage | hopeful; positive; upbeat |
| Organized | adjective | Conscientiousness facet | systematic; structured; efficient |
| Orderly | adjective | Conscientiousness | tidy; neat; methodical |
| Observant | adjective | common usage | perceptive; attentive; watchful |
| Objective | adjective | common usage | impartial; unbiased; neutral |
| Opinionated | adjective | common usage | dogmatic; assertive; strong-minded |
| Obliging | adjective | common usage | accommodating; helpful; cooperative |
| Obedient | adjective | common usage/clinical | compliant; dutiful; submissive |
| Obsessive | adjective | clinical/common usage | fixated; preoccupied; compulsive |
| Obsessive-compulsive | adjective | clinical term (DSM usage) | ritualistic; perfectionistic; compulsive |
| Oppositional | adjective | clinical/common usage | contrary; defiant; resistant |
| Opportunistic | adjective | personality literature | self-serving; pragmatic; exploitative |
| Overconfident | adjective | common usage | cocky; arrogant; complacent |
| Overbearing | adjective | common usage | domineering; bossy; autocratic |
| Overcontrolled | adjective | clinical/personality research | restrained; inhibited; rigid |
| Oversensitive | adjective | common usage | touchy; hypersensitive; thin-skinned |
| Overcritical | adjective | common usage | hypercritical; fault-finding; judgmental |
| Obstinate | adjective | common usage | stubborn; unyielding; persistent |
| Obstreperous | adjective | common usage/dictionary | rowdy; unruly; boisterous |
| Ornery | adjective | colloquial/common usage | irritable; cantankerous; grouchy |
| Ostentatious | adjective | common usage | showy; flamboyant; pretentious |
| Original | adjective | common usage | innovative; inventive; creative |
| Odd | adjective | clinical/common usage | peculiar; eccentric; unconventional |
| Orthodox | adjective | common usage | conventional; traditional; conservative |
| Overcautious | adjective | common usage | risk-averse; wary; cautious |
| Overprotective | adjective | common usage | smothering; controlling; anxious |
| Obsequious | adjective | common usage | sycophantic; servile; ingratiating |
| Obtuse | adjective | common usage | slow-witted; insensitive; dull |
| Other-directed | adjective | social psychology/literature | people-pleasing; externally oriented |
| Overenthusiastic | adjective | common usage | eager; zealous; excitable |
| Overemotional | adjective | common usage | emotional; reactive; volatile |
| Oblivious | adjective | common usage | unaware; inattentive; distracted |
Descriptions
Openness
Tendency to seek new ideas, experiences, and art; shows curiosity, intellectual interest, and receptivity to change.
Open-minded
Willing to consider different perspectives and revise beliefs when presented with reasoned evidence.
Outgoing
Energetic sociability and ease in groups; seeks interaction, conversation, and external stimulation.
Outspoken
Directly expresses opinions without much filtering; comfortable saying what one thinks even when controversial.
Optimistic
Tendency to expect favorable outcomes and focus on opportunities rather than setbacks.
Organized
Prefers order, planning, and clear systems; keeps tasks, time, and space well arranged.
Orderly
Habitually neat and systematic; values routines and predictable arrangements.
Observant
Quick to notice details, social cues, and changes in the environment.
Objective
Makes decisions based on facts and logic rather than personal feelings.
Opinionated
Holds firm beliefs and expresses them confidently, often resistant to changing views.
Obliging
Willing to assist or accommodate others; prioritizes cooperation and supportiveness.
Obedient
Follows rules, authority, or social expectations; values conformity and order.
Obsessive
Persistent, repetitive thoughts or behaviors; strong focus that can interrupt flexibility.
Obsessive-compulsive
Shows rigid rituals, intrusive thoughts, and repetitive behaviors; ranges from personality style to disorder.
Oppositional
Frequently challenges rules or authority and resists requests or expectations.
Opportunistic
Seizes chances for personal gain, often adjusting morals to benefit oneself.
Overconfident
Excessive certainty in abilities or judgments, often underestimating risks or feedback.
Overbearing
Imposes will on others, controls decisions, and disregards others’ autonomy.
Overcontrolled
Excessive self-restraint in emotion and behavior; avoids spontaneity and intense expression.
Oversensitive
Quickly hurt by criticism or perceived slights; may overreact to feedback.
Overcritical
Frequently finds faults in others or situations, often expecting unrealistically high standards.
Obstinate
Refuses to change opinions or behavior despite persuasion; resists pressure.
Obstreperous
Noisily defiant or difficult; resists control with loud, disruptive behavior.
Ornery
Habitually cranky, argumentative, or stubborn in a gruff way.
Ostentatious
Seeks attention through conspicuous displays of wealth, status, or style.
Original
Prone to novel ideas, unique perspectives, and unconventional approaches.
Odd
Unusual or eccentric behavior or beliefs that deviate from social norms.
Orthodox
Adheres strongly to established beliefs, rules, or religious/traditional practices.
Overcautious
Avoids risk and acts hesitantly; prefers safety and thorough planning.
Overprotective
Excessively shields others from perceived harm, limiting independence and autonomy.
Obsequious
Excessively eager to please or flatter authority, often insincerely.
Obtuse
Appears slow to understand or insensitive to subtle social cues; often used pejoratively.
Other-directed
Guided more by others’ expectations and approval than by internal values.
Overenthusiastic
Displays excessive enthusiasm that may overwhelm or derail situations.
Overemotional
Responds with strong, often exaggerated emotions; may struggle with regulation.
Oblivious
Habitually unaware of social cues, others’ feelings, or surroundings.