(a) As an affirmative reply to a direct or an indirect question: yes; also, as an affirmation of the truth or correctness of an assertion, a proposition, a negation, etc., usu. presented as a question or rhetorical question: it is so, yes; (b) as an indication of agreement, assent, or acquiescence to an imposed condition, a demand, a request, an invitation to act, or a similar jussive or hortatory utterance: so be it, that is agreed, yes; (c) as a contradiction of the answer (expressed or implied) to a question or of a statement presented as a question, usu. with a negative: on the contrary, yes but things are otherwise; oh yes I do, we are, etc.; (d) as an introductory word of response implying impatience or anxiety: yes, yes; ?also, implying doubt or skepticism: well, yes; (e) as an introductory word of response indicating mere emphasis or willingness to answer: yes.

In selected verb phrases: (a) seien ~, to take an affirmative position, assert that something is or will be so;—sometimes with ellipsis of verb; also, give (sb.) an affirmative response to a request; (b) sweren ~, to swear that something is indeed so; make a vow (to sb.) that one will do something; (c) trouen ~, to think that something is the case; also, after a denial: think otherwise, disagree that something is so [1st quot.].