Definition of "speak for" []

• Used other than as an idiom: see speak,‎ for. (verb)
• To speak on somebody's behalf. (verb)
• To claim, reserve, or occupy. (verb)
• To represent an intrinsic quality (verb)

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• "Roman is big and language-deaf; his mouth does not want to contort to form alien sounds, and he lets Malvina speak for both of them."
• "One of their number, an old Macedonian cavalryman named Callines, came forward to speak for the men."
• "It had to be somebody who could come back from a Deputies Committee, place a call to the secretary or walk down the hall, and get in to see him immediately and get his reactions, or could speak for him in the meetings authoritatively, Gates explained."