nonchalant
/icons/point.icon COOL, COMPOSED, COLLECTED, UNRUFFLED, IMPERTURBABLE, NONCHALANT mean free from agitation or excitement.
COOL may imply calmness, deliberateness, or dispassionateness.
e.g. kept a cool head
COMPOSED implies freedom from agitation as a result of self-discipline or a sedate disposition.
e.g. the composed pianist gave a flawless concert
COLLECTED implies a concentration of mind that eliminates distractions especially in moments of crisis.
e.g. the nurse stayed calm and collected
UNRUFFLED suggests apparent serenity and poise in the face of setbacks or in the midst of excitement.
e.g. harried but unruffled
IMPERTURBABLE implies coolness or assurance even under severe provocation.
e.g. the speaker remained imperturbable despite the heckling
NONCHALANT stresses an easy coolness of manner or casualness that suggests indifference or unconcern.
e.g. a nonchalant driver
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adjective
(of a person or manner) feeling or appearing casually calm and relaxed; not displaying anxiety, interest, or enthusiasm:
〈様子･態度などが〉無関心な; 無頓着な, 気にしない; 平然とした, 冷淡な.
e.g. she gave a nonchalant shrug.
ORIGIN
mid 18th century: from French, literally ‘not being concerned’, from the verb nonchaloir.