Bringing two different things together with an explicit word, such as "like", "just as", or "seems". Unlike metaphor, the simile makes clear that they are two things.
In The Posthumous Memoirs of Brás Cubas
Virgília drew back, as if it were a corpse's kiss.
"As if it were a corpse's kiss" explicitly links Brás's gesture to the coldness of death, and Virgília's recoil shows that the kiss does not warm.
Chapters LXXXVIII to C: Viegas, Quincas Borba, and the Anonymous Letter, the narrator
I was not shaken: I took them to the cemetery, the way one takes money to a bank
Chapters CI to CXVI: The Wall, the Weld, and the Old Leaves, the narrator
The tax on pain is like Vespasian's coin; it does not smell of its origin, and one collects it as much from evil as from good
Chapters CXXXVII to CLX: The Cap, the Ministry, and the Denials, the narrator
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