mid-15c., "frightened, alarmed, startled," past-participle adjective from scare (v.). Emphatic scared stiff is recorded by 1900; scared shitless by 1936. Scaredy-cat "timid person" first attested 1906.
1590s, "frighten, terrify suddenly," an unusual alteration of Middle English skerren "to frighten" someone (late 12c.), from Old Norse skirra "to frighten; to shrink from, shun; to prevent, avert," which is related to skjarr "timid, shy, afraid of," but of unknown origin.
In Scottish also skair, skar, which seem to track closer to the word's expected development, and in dialect skeer, skear. Intransitive meaning "become frightened, be scared" is from 14c.; the specific sense of "be alarmed by rumor" is from 1900.
To scare away "drive off by frightening" is from 1650s. To scare up "procure, obtain, find, bring to light" is recorded by 1846, American English, from notion of rousing game from cover. Related: Scared; scaring.
"trembling from fear or terror," 1640s, from Latin trepidus "scared" (see trepidation). Related: Trepidly; trepidness.
c. 1600, from French trepidation (15c.) and directly from Latin trepidationem (nominative trepidatio) "agitation, alarm, trembling," noun of action from past-participle stem of trepidare "to tremble, hurry," from trepidus "alarmed, scared," from PIE *trep- (1) "to shake, tremble" (source also of Sanskrit trprah "hasty," Old Church Slavonic trepetati "to tremble"), related to *trem- (see tremble (v.)). Related: Trepidacious (1915).
late 14c., "causing terror, awe, or dread; frightful," from Old French terrible (12c.), from Latin terribilis "frightful," from terrere "fill with fear," from PIE root *tros- "to make afraid" (source also of Sanskrit trasanti "to tremble, be afraid," Avestan tarshta "scared, afraid," Greek treëin "to tremble, be afraid," Lithuanian trišėti "to tremble, shiver," Old Church Slavonic treso "I shake," Middle Irish tarrach "timid"). Weakened sense of "very bad, awful" is first attested 1590s.
late 13c., "a beginning, act or fact of coming into existence," from Old French comencement "beginning, start" (Modern French commencement), from comencier "to begin, to start" (see commence).
Meaning "school graduation ceremony" attested by 1850, American English, originally in colleges, in reference to the ceremonies by which members of the graduating class are made ("begin to be") bachelors, masters, etc. (commencement in the sense of "entrance upon the privileges of a master or doctor in a university" is from late 14c.) ; thence extended to graduation ceremonies of academies and lower schools.
I know what you are thinking of — the class members grouped in a semicircle on the stage, the three scared boys in new ready-made black suits, the seventeen pretty girls in fluffy white dresses (the gowns of the year), each senior holding a ribbon-tied manuscript bulging with thoughts on "Beyond the Alps Lies Italy," "Our Ship is Launched — Whither Shall it Sail?" and similar topics. [Charles Moreau Harger, "The Real Commencement," New Outlook, May 8, 1909]
also brinksmanship (with unetymological -s-), 1956, a construction based on salesmanship, sportsmanship, etc.; from brink (n.). The image of the brink of war dates to at least 1829 (John Quincy Adams).
In the Cold War it was associated with the policies advocated by John Foster Dulles, U.S. Secretary of State 1953-1959. The word springs from Dulles' description of his philosophy in a magazine interview [with Time-Life Washington bureau chief James Shepley] in early 1956:
The ability to get to the verge without getting into the war is the necessary art. If you cannot master it, you inevitably get into war. If you try to run away from it, if you are scared to go to the brink, you are lost.
The quote was widely criticized by the Eisenhower Administration's opponents, and the first attested use of brinkmanship seems to have been in such a disparaging context, a few weeks after the magazine interview appeared, by Democratic presidential candidate Adlai Stevenson criticizing Dulles for "boasting of his brinkmanship — the art of bringing us to the edge of the nuclear abyss."
contemptuous nickname in U.S. politics for Northern Democrats who worked in the interest of the South before the Civil War, by 1833. It was taken to mean "man who allows himself to be molded," but that probably was not the original image. The source is an 1820 speech by John Randolph of Roanoke, in the wake of the Missouri Compromise.
Randolph, mocking the northerners intimidated by the South, referred to a children's game in which the players daubed their faces with dough and then looked in a mirror and scared themselves. [Daniel Walker Howe, "What Hath God Wrought," 2007]
Randolph had used the term dough-face in the sense "mask of dough" in Congressional debates as far back as February 1809 ("... it is something like dressing ourselves up in a dough-face and winding-sheet to frighten others ....").
However, the expression has been explained as referring to "the pale doughy faces of his frightened opponents" [Craigie], to a "person who is pliable and, as it were, made of dough" [Century Dictionary], or even "to liken them in timidity to female deer," which is frightened at her own shadow [The Port Folio, 1820]. Dough-faced in the sense "cowardly" is attested in a text from 1773, so there might be a convergence of senses.