barker

The word 'barker' is a straightforward agent noun formation from the verb 'bark'. The verb 'bark' itself has ancient Germanic origins, traceable to the Proto-Germanic berkaną, which imitated the sharp, explosive sound made by dogs. The addition of the agent suffix '-er', a productive morpheme in English since its Old English stage, creates a noun meaning "one who barks." Its primary modern sense, referring to a person who shouts advertisements, is a metaphorical extension from the late 17th century, drawing a direct analogy between the loud, repetitive, and attention-seeking vocalizations of a dog and those of a human promoter.

Structure: bark (to make a sharp, loud sound) + er (agent suffix) - bark: From Old English beorcan, meaning "to bark." Its functional role is the core verb denoting the action. - er: A native English agentive suffix from Old English -ere, used to form nouns indicating a person or thing that performs the action of the verb.