early 14c., "to lay claim to," from Latin acclamare "to cry out at" (in Medieval Latin "to claim"), from ad "to, toward" (see ad-) + clamare "cry out" (from PIE root *kele- (2) "to shout"). The meaning "to applaud" is recorded by 1630s. The spelling has been conformed to claim. Related: Acclaimed; acclaiming; acclamatory.

1540s, "act of shouting or applauding in approval," from Latin acclamationem (nominative acclamatio) "a calling, exclamation, shout of approval," noun of action from past-participle stem of acclamare "to call to, cry out at, shout approval or disapproval of," from assimilated form of ad "to, toward" (see ad-) + clamare "cry out" (from PIE root *kele- (2) "to shout"). As a method of spontaneous approval of resolutions, etc., by unanimous voice vote, by 1801, probably from the French Revolution.

"the Enlightenment," 1801, from German Aufklärung (18c.), literally "enlightenment," from aufklären "to enlighten" (17c.), from auf "up" (from PIE root *upo "under," also "up from under") + klären "to clear," from Latin clarus (see clear (adj.)).

c. 1200, calender, "the year as divided systematically into days and months;" mid-14c. as "table showing divisions of the year;" from Old French calendier "list, register," from Latin calendarium "account book," from calendae/kalendae "the calends" the first day of the Roman month, when debts fell due and accounts were reckoned.

This is from calare "to announce solemnly, call out," as the priests did in proclaiming the new moon that marked the calends, from PIE root *kele- (2) "to shout." In Rome, new moons were not calculated mathematically but rather observed by the priests from the Capitol; when they saw it, they would "declare" the number of days till the nones (five or seven, depending on the month). The word was taken by the early Church for its register list of saints and their feast days. The meaning "list of documents arranged chronologically" is from late 15c.

The -ar spelling in English is from 17c., to differentiate it from the now-obscure calender "cloth-presser." Related: Calendarial; calendary.

1680s, "disposition of light and dark in a picture," literally "bright-dark," from Italian chiaro "clear, bright" (from Latin clarus; see clear (adj.)) + oscuro (from Latin obscurus; see obscure (adj.)). Related: Chiaroscurist.

c. 1300, "to call, call out; to ask or demand by virtue of right or authority," from accented stem of Old French clamer "to call, name, describe; claim; complain; declare," from Latin clamare "to cry out, shout, proclaim," from PIE root *kele- (2) "to shout." Related: Claimed; claiming.

Meaning "to maintain as true, assert a belief or opinion" is from 1864 ("A common use, regarded by many as inelegant" - Century Dictionary, 1895); claim properly should not stray too far from its true meaning of "to demand recognition of a right." Specific sense "to make a claim" (on an insurance company) is from 1897.

fem. proper name, from French claire, fem. of clair literally "light, bright," from Latin clarus "clear, bright, distinct" (see clear (adj.); also compare Clara).

"paranormal gift of seeing things out of sight," 1837, from special use of French clairvoyance (16c., from Old French clerveans, 13c.) "quickness of understanding, sagacity, penetration," from clairvoyant "clear-sighted, discerning, judicious" (13c.), from clair (see clear (adj.)) + voyant "seeing," present participle of voir, from Latin videre "to see" (from PIE root *weid- "to see"). A secondary sense in French is the main sense in English.

"having psychic gifts, characterized by powers of clairvoyance," 1837, earlier "having insight" (1670s), from special use of French clairvoyant "clear-sighted, discerning, judicious" (13c.), from clair (see clear (adj.)) + voyant "seeing," present participle of voir, from Latin videre "to see" (from PIE root *weid- "to see"). Related: Clairvoyantly.

late 14c., "a great outcry," also figurative, "loud or urgent demand," from Old French clamor "call, cry, appeal, outcry" (12c., Modern French clameur), from Latin clamor "a shout, a loud call" (either friendly or hostile), from clamare "to cry out" (from PIE root *kele- (2) "to shout").