should imperfect of Shall. [OE. sholde, shulde, scholde, schulde, AS. scolde, sceolde. See Shall.]

Used as an auxiliary verb, to express a conditional or contingent act or state, or as a supposition of an actual fact; also, to express moral obligation (see Shall); e. g.: they should have come last week; if I should go; I should think you could go.

“You have done that you should be sorry for.” Shak.

Syn. – See Ought.