(Irregular preterit, past participle: understood).
1 > To perceive mentally, as of an idea | SYN: realize, see.
2 > To know and comprehend the nature or meaning of.
3 > To make sense of a language, although one may not be able to produce it | SYN: read, interpret, translate.
4 > To believe to be the case | SYN: gather, infer.