the.com/chatterer

means A person who talks constantly, often about trivial things — or, in zoology, any of several bird species (like waxwings) literally named for their chattering calls.

from Straightforward agentive formation: 'chatter' plus '-er.' 'Chatter' itself is echoic — a word built to imitate the quick, clicking rattle of teeth, birds, or rapid idle talk, likely with roots stretching back through Middle English to similar sound-mimicking forms in older Germanic speech. No hidden plot here — it's onomatopoeia doing exactly what it sounds like.