GRE nebulous Definition Vague or unclear in form or meaning. Example "He had a nebulous idea of what he wanted to do after graduation." Sign in to save GRE Quiz → ← nebula necessitate → Study tips featuring "nebulous" Write GRE Words Into Your Own Sentences Related words GRE swill GRE taper GRE testy GRE abacus SAT abase GRE abash GRE abate GRE abbreviate GRE abbreviation SAT abdicate SAT abdomen GRE abduct