From c. 1300 as "physical shape (of something), contour, outline," of a person, "shape of the body;" also "appearance, likeness;" also "the imprint of an object." From c. 1300 as "correct or appropriate way of doing something; established procedure; traditional usage; formal etiquette." Mid-14c. as "instrument for shaping; a mould;" late 14c. as "way in which something is done," also "pattern of a manufactured object." Used widely from late 14c. in theology and Platonic philosophy with senses "archetype of a thing or class; Platonic essence of a thing; the formative principle." From c. 1300 in law, "a legal agreement; terms of agreement," later "a legal document" (mid-14c.). Meaning "a document with blanks to be filled in" is from 1855. From 1590s as "systematic or orderly arrangement;" from 1610s as "mere ceremony." From 1550s as "a class or rank at school" (from sense "a fixed course of study," late 14c.). Form-fitting (adj.) in reference to clothing is from 1893.
c. 1400, requisicioun, "a request, an act of requesting or demanding," from Old French requisicion (12c.) and directly from Medieval Latin requisitionem (nominative requisitio) "examination, a searching," noun of action from past-participle stem of Latin requirere (past participle requisitus) "seek to know, ask, ask for" (see require).
The meaning "action of formally calling upon someone to perform some action, etc." is by 1550s, originally legal. The sense of "action of requiring a certain amount of something to be furnished" is by 1776.
"demand or require (something) to be furnished" for military or public purposes, 1837, from requisition (n.). Related: Requisitioned; requisitioning.
"form again, remake, reconstruct, re-create or re-establish," mid-14c., from re- "back, again" + form (v.). Intransitive sense of "form again, get into order or line again" also is from mid-14c. Spelled with a hyphen from 17c. to distinguish it from the specific sense in reform; this is the original meaning of that word, still in use but now with full pronunciation of the prefix. Related: Re-formed; re-forming; re-formation.
"one who makes a requisition," 1877, agent noun from requisition (v.). Earlier was requisitionist (1819).
1520s, in grammar, "expressing command," used of the form of a verb which expresses command, entreaty, advice, or exhortation, from Late Latin imperativus "pertaining to a command," from imperat-, past participle stem of imperare "to command, requisition," from assimilated form of in- "into, in" (from PIE root *en "in") + parare "to arrange, prepare, adorn" (from PIE root *pere- (1) "to produce, procure").
1520s, "request, requisition" (a sense now obsolete), from require + -ment. Meaning "things required, a need, something necessary" is from 1660s. Meaning "that which must be accomplished, necessary condition" is by 1841. Related: Requirements. Fowler points out that requirement "means properly a need" and requisite "a needed thing," though the distinction is a fine one.
That which is required by the nature of the case, or is only indirectly thought of as required by a person, is called a requisite ; that which is viewed as required directly by a person or persons is called a requirement ...; a requisite is more often material than a requirement ; a requisite may be a possession or something that may be viewed as a possession, but a requirement is a thing to be done or learned. [Century Dictionary, 1895]