"Last night was one of their cabal nights; they have 'em three times a-week, and meet by turns at one another's apartments, where they come together like the coroner's inquest, to sit upon the murdered reputations of the week." (Act I, Scene I) (Simile/Metaphor)
This quote includes both simile - ""like the coroner's inquest" - and metaphor - "to sit upon the murdered reputations of the week." The quote pokes fun at the women in the play taking gossip as seriously as if it were a profession, though the men in the play certainly engage in gossip and reputation-mongering as well. The image of a "murdered reputation" is an especially important one to the play, as a fear of social murder or suicide is what keeps the characters in the play churning with schemes and secrets.
"Friendship without freedom is as dull as love without enjoyment, or wine without toasting." ((Act I, Scene II) (Simile)
Similes, metaphors, imagery, and highly flowery rhetorical language are all very important to Restoration Comedies. The plays thrive on wit, and the characters and their relationships are heightened by their ability to rattle off sweet or biting comparisons, especially concerning themes of friendship, love, sex, and drinking, as in this quote.
"Thou art as quick as fire in a frosty morning" (Act I, Scene II) (Simile)
Again, this simile is quite typical of Restoration Comedy, and is almost metatheatrical as it comments on the very wittiness of another character, though perhaps sarcastically.
"I have inquired after you, as after a new fashion." (Act II, Scene II) (Simile)
This quote is highly fitting for the play, as the characters do ask after one another and even pursue one another in ways focused on reputation and societal standing, like an attention to fashion. Ms. Millamant even forwards the comparison, saying that finding a wife by asking her husband "were like inquiring after an old fashion" - meaning that it is the wrong thing to do, as husbands likely will not be up to date or aware of the whereabouts, among other things, of their wives.
"They could neither of 'em speak for rage, and so fell a sputtering at one another like two roasting apples." (Act III, Scene III) (Simile)
This simile is simply in good fun, and makes light of the situation going on offstage. Using this colorful language, then, creates a humorous image even of something unseen, and adds anticipation to seeing the drunken men come onstage.