Investigated whether metaphors such as "Cigarettes are timebombs" are understood directly, as in S. Glucksberg's class-inclusion model (Glucksberg and B. Keysar, 1990), or by transforming them into similes ("Cigarettes are like timebombs"), as in G. Miller's (1979) comparison model. The present 2 studies tested these competing theories using reaction time latencies calculated during a modified context-sentence verification task. 48 undergraduates were presented serially with 48 2-sentence sets. The priming sentence was a simile, a metaphor, or a filler sentence. The task involved reading the priming sentence and pressing a key to indicate comprehension, then reading a test sentence and indicating whether it logically followed or did not logically follow the prime sentence. Results show that metaphor sentences were comprehended significantly faster than were simile sentences and that this difference was not accounted for by sentence length. There were no differences in response times between prime sentence types or test sentence types. The results therefore are most consistent with Glucksberg's class-inclusion model.