Explanation
Often appears as a past form of ～ぶる, meaning 'acted/pretended like ~' (or literally 'hit/bashed', depending on context).
Formation
Noun/Adjective + ぶる → ぶった (past tense), e.g., 偉そうぶった, 大人ぶった
Detailed explanation
The verb ～ぶる means 'to act/behave as if one is ~' (e.g., 偉そうにぶる: 'to act all high and mighty'). In its past tense, ～ぶった can describe someone who acted or pretended in a certain way. Be aware that ぶった can also simply be 'hit' (past tense of 打つ/ぶつ) depending on the kanji/spelling, but as a grammar pattern, it’s about 'putting on airs.'
Examples
Kare wa nandemo shitteiru ka no you ni butta taido o toru.
He takes on an attitude as though he knows everything.
Erasou butta monoii o sareru to, sukoshi hara ga tatsu.
It irritates me when he speaks in such a high-and-mighty way.
Kanojo wa otona butta kuchou de hanashite iru ga, jitsu wa mada koukousei da.
She’s speaking in a very grown-up manner, but she’s actually still in high school.
Ii ko butta taido o toranakute mo ii yo.
You don't have to pretend to be such a goody-goody.
Practice
Grammar content sourced from hanabira.org.