Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class V. Words Releasing to the Voluntary Powers
Division (I) Individual Volition
Section II. Prospective Volition
1. Conceptional Volition

630. Requirement.

   NOUN:REQUIREMENT, need, wants, necessities; necessaries, – of life; stress, exigency, pinch, sine quâ non [L.], matter of necessity; case of need, case of life or death.
  desideratum (desire) [See Desire]; want (deficiency) [See Insufficiency].
  NEEDFULNESS, essentiality, necessity, indispensability, urgency, prerequisite; the least one can -do, – require.
  REQUISITION (request) [See Request] (exaction) [See Command]; run; demand for, call for.
  CHARGE, claim, command, injunction, mandate, order, precept, ultimatum.
   VERB:REQUIRE, need, want, have occasion for; not be able to do without, not able to dispense with; prerequire.
  BE NECESSARY &c. adj.; stand in need of; lack [See Insufficiency]; desiderate; desire [See Desire].
  RENDER NECESSARY, necessitate, create a necessity for, call for, put in requisition; make a requisition (ask for) [See Request], (demand) [See Command].
   ADJECTIVE:NECESSARY; required &c. v.; requisite, needful, imperative, essential, indispensable, prerequisite; called for; in demand, in request.
  in want of; destitute of [See Insufficiency].
  URGENT, exigent, pressing, instant, crying, absorbing.
   ADVERB:OF NECESSITY; ex necessitate rei [L.] (necessarily) [See Necessity]; out of -stern necessity, – bitter need; at a pinch.
  1. There is no time to lose.
  2. It cannot be -spared, – dispensed with.
  3. Mendacem memorem esse oportet.—Quintilian
  4. Necessitas non habet legem.
  5. Nec tecum possum vivere nec sine te.—Martial
  6. Needs must when the devil drives.
  7. Necessity has no law.—Rabelais
  8. Necessity’s sharp pinch.—Lear
  9. Socrates said, “those who want fewest things are nearer to the gods.”—Diogenes Laertius