A person or animal that babbles; someone who talks excessively, incoherently, or without saying anything meaningful.
From 'babble' plus the suffix -er, indicating an agent noun (one who does the action). The suffix -er is the most common English way to convert verbs into nouns describing people who perform those actions.
Interestingly, 'babbler' also refers to a family of Asian birds known for their loud, continuous chattering—so the word naturally extends from humans to animals because the behavior is genuinely similar across species.
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