Occasionally used attributively before a noun.
The uttered threat made everyone uneasy.
Произнесённая угроза заставила всех нервничать.
Used as the past participle of the verb 'utter' functioning adjectivally.
Her apology, uttered softly, was barely audible.
Её извинение, произнесённое тихо, едва было слышно.