Annoying — grating, in your face.
Blunter than 面倒くさい, which is about effort. うざい is about irritation: a person who will not stop talking, a noise, a pop-up ad. Often thrown out as a single word.
Shortened from うざったい, a regional word that spread nationally through young speakers.
Genuinely rude about a person — closer to "he’s obnoxious" than "he’s a bit much". Do not aim it at anyone senior.
Reading a definition isn't the same as saying it to someone. Lingo Kaiava is a voice tutor set to Japanese — it uses うざい the way locals do, corrects you in the moment, and never "fixes" the way real people actually talk into textbook Japanese.
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