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definitions

should

[shoo d]
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auxiliary verb
  1. simple past tense of shall.
  2. (used to express condition): Were he to arrive, I should be pleased.
  3. must; ought (used to indicate duty, propriety, or expediency): You should not do that.
  4. would (used to make a statement less direct or blunt): I should think you would apologize.

Origin of should

Middle English sholde, Old English sc(e)olde; see shall
Can be confusedcould should would (see usage note at the current entry)

Synonyms for should

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3. See must1.

Usage note

Rules similar to those for choosing between shall and will have long been advanced for should and would, but again the rules have had little effect on usage. In most constructions, would is the auxiliary chosen regardless of the person of the subject: If our allies would support the move, we would abandon any claim to sovereignty. You would be surprised at the complexity of the directions.
Because the main function of should in modern American English is to express duty, necessity, etc. ( You should get your flu shot before winter comes ), its use for other purposes, as to form a subjunctive, can produce ambiguity, at least initially: I should get my flu shot if I were you. Furthermore, should seems an affectation to many Americans when used in certain constructions quite common in British English: Had I been informed, I should (American would ) have called immediately. I should (American would ) really prefer a different arrangement. As with shall and will, most educated native speakers of American English do not follow the textbook rule in making a choice between should and would. See also shall.

shall

[shal; unstressed shuh l]
auxiliary verb, present singular 1st person shall, 2nd shall or (Archaic) shalt, 3rd shall, present plural shall; past singular 1st person should, 2nd should or (Archaic) shouldst or should·est, 3rd should, past plural should; imperative, infinitive, and participles lacking.
  1. plan to, intend to, or expect to: I shall go later.
  2. will have to, is determined to, or definitely will: You shall do it. He shall do it.
  3. (in laws, directives, etc.) must; is or are obliged to: The meetings of the council shall be public.
  4. (used interrogatively in questions, often in invitations): Shall we go?

Origin of shall

before 900; Middle English shal, Old English sceal; cognate with Old Saxon skal, Old High German scal, Old Norse skal; compare German soll, Dutch zal
Can be confusedcan may shall will (see usage note at can1) (see usage note at the current entry)

Usage note

The traditional rule of usage guides dates from the 17th century and says that to denote future time shall is used in the first person ( I shall leave. We shall go ) and will in all other persons ( You will be there, won't you? He will drive us to the airport. They will not be at the meeting ). The rule continues that to express determination, will is used in the first person ( We will win the battle ) and shall in the other two persons ( You shall not bully us. They shall not pass ). Whether this rule was ever widely observed is doubtful. Today, will is used overwhelmingly in all three persons and in all types of speech and writing both for the simple future and to express determination. Shall has some use in all persons, chiefly in formal writing or speaking, to express determination: I shall return. We shall overcome. Shall also occurs in the language of laws and directives: All visitors shall observe posted regulations. Most educated native users of American English do not follow the textbook rule in making a choice between shall and will. See also should.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for should

enjoy, undergo, consider, feel, experience, leave, see, know, allow, permit, need, become, suffer, will, let, tolerate, sustain, entertain, must, shall
British Dictionary definitions for should

should

verb
  1. the past tense of shall : used as an auxiliary verb to indicate that an action is considered by the speaker to be obligatory (you should go) or to form the subjunctive mood with I or we (I should like to see you; if I should be late, go without me)See also shall

Word Origin for should

Old English sceold; see shall

usage

Should has, as its most common meaning in modern English, the sense ought as in I should go to the graduation, but I don't see how I can. However, the older sense of the subjunctive of shall is often used with I or we to indicate a more polite form than would: I should like to go, but I can't. In much speech and writing, should has been replaced by would in contexts of this kind, but it remains in formal English when a conditional subjunctive is used: should he choose to remain, he would be granted asylum

shall

verb past should (takes an infinitive without to or an implied infinitive)
  1. (esp with I or we as subject) used as an auxiliary to make the future tensewe shall see you tomorrow Compare will 1 (def. 1)
  2. (with you, he, she, it, they, or a noun as subject)
    1. used as an auxiliary to indicate determination on the part of the speaker, as in issuing a threatyou shall pay for this!
    2. used as an auxiliary to indicate compulsion, now esp in official documentsthe Tenant shall return the keys to the Landlord
    3. used as an auxiliary to indicate certainty or inevitabilityour day shall come
  3. (with any noun or pronoun as subject, esp in conditional clauses or clauses expressing doubt) used as an auxiliary to indicate nonspecific futurityI don't think I shall ever see her again; he doubts whether he shall be in tomorrow

Word Origin for shall

Old English sceal; related to Old Norse skal, Old High German scal, Dutch zal

usage

The usual rule given for the use of shall and will is that where the meaning is one of simple futurity, shall is used for the first person of the verb and will for the second and third: I shall go tomorrow; they will be there now. Where the meaning involves command, obligation, or determination, the positions are reversed: it shall be done; I will definitely go. However, shall has come to be largely neglected in favour of will, which has become the commonest form of the future in all three persons
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for should

c.1200, from Old English sceolde, past tense of sceal (see shall). Preserves the original notion of "obligation" that has all but dropped from shall.

shall

v.

Old English sceal, Northumbrian scule "I owe/he owes, will have to, ought to, must" (infinitive sculan, past tense sceolde), a common Germanic preterite-present verb (along with can, may, will), from Proto-Germanic *skal- (cf. Old Saxon sculan, Old Frisian skil, Old Norse and Swedish skola, Middle Dutch sullen, Old High German solan, German sollen, Gothic skulan "to owe, be under obligation;" related via past tense form to Old English scyld "guilt," German Schuld "guilt, debt;" also Old Norse Skuld, name of one of the Norns), from PIE root *skel- (2) "to be under an obligation."

Ground sense of the Germanic word probably is "I owe," hence "I ought." The sense shifted in Middle English from a notion of "obligation" to include "futurity." Its past tense form has become should (q.v.). Cognates outside Germanic are Lithuanian skeleti "to be guilty," skilti "to get into debt;" Old Prussian skallisnan "duty," skellants "guilty."

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with should

should

In addition to the idiom beginning with should

  • should have stood in bed, I

also see:

  • (should) get one's head examined
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.