A person who boasts; someone who talks excessively or too proudly about their achievements, possessions, or abilities.
Boast + -er (suffix creating agent nouns). Emerged in Middle English to describe people prone to excessive bragging, combining the verb 'boast' with a standard suffix for 'one who does X.'
Every culture has a word for someone who brags too much, but English 'boaster' is fun because 'boast' might come from an Old Norse root meaning 'to threaten'—so a boaster is basically someone who threatens you with how great they are!
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