Troublesome, a hassle — and also "to trouble someone."
Works as an adjective ("太麻烦了" = too much hassle) and as a polite verb: "麻烦你" prefaces a request and is one of the most useful politeness moves in Mandarin, closer to "sorry to bother you, could you…"
Learning it only as "annoying" wastes it. The polite-request use is what will actually make you sound fluent.
Reading a definition isn't the same as saying it to someone. Lingo Kaiava is a voice tutor set to Chinese — it uses 麻烦 the way locals do, corrects you in the moment, and never "fixes" the way real people actually talk into textbook Chinese.
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