A person who assents or agrees to something; one who gives approval or consent.
From 'assent' + '-er' (agent suffix). The '-er' suffix transforms a verb into a noun describing the person who performs the action, following the productive pattern of English word formation.
While we use 'assenter' rarely today, it perfectly captures the person in a meeting who nods along and says 'yes'—it's distinctly different from 'supporter' because it's passive agreement rather than active advocacy.
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