Origin: 1350–1400; (noun, adj.) Middle English calm(e) < Italian calma (noun), calmo (adj.) < Late Latin cauma summer heat (with l perhaps from Latin calēre to be hot) < Greek kaûma (stem kaumat-) burning heat; akin to kaíein to burn (see caustic); (v.) Middle English calmen < Italian calmare, derivative of the noun
Synonyms 1. quiet, motionless. 3. placid, peaceful, serene, self-possessed. Calm,collected,composed,cool imply the absence of agitation. Calm implies an unruffled state, especially under disturbing conditions: calm in a crisis. Collected implies complete inner command of oneself, usually as the result of an effort: He remained collected in spite of the excitement. One who is composed has or has gained dignified self-possession: pale but composed. Cool implies clarity of judgment along with apparent absence of strong feeling or excitement, especially in circumstances of danger or strain: so cool that he seemed calm. 7. still, quiet, tranquilize; allay, assuage, mollify, soothe, soften.
late 14c., from O.Fr. calme, traditionally from O.It. calma, from L.L. cauma "heat of the mid-day sun" (in Italy, a time when everything rests and is still), from Gk. kauma "heat" (especially of the sun), from kaiein "to burn." Spelling influenced by L. calere "to be hot." Figurative application to social