Subjoined or added to something before said or written.In grammar, noting that mode of the verb by which is expressed condition, hypothesis, or contingency, and which is generally used in a clause subjoined or subordinate to another clause or verb, and preceded by one of certain conjunctions, especially (in English) if or though: as in the sentence “if that be the case, then I am wrong.”n. In grammar, the subjunctive mode.