- 1to guess or suppose something using the evidence you have, without definitely knowing synonym conjecture
- 2 From the looks on their faces, I surmised that they had had an argument.
NAmE//sərˈmaɪz//[transitive, intransitive] surmise (something) surmise (that)… surmise what, where, etc… + speech (formal)Verb Forms present simple I / you / we / they surmise
he / she / it surmises
past simple surmised
-ing form surmising