If something irks you, it makes you feel annoyed — usually in a small, repeated way, not a huge burst of anger. A tap that keeps dripping can irk you. A tiny habit someone will not stop can irk you. The feeling is closer to “this keeps rubbing me the wrong way” than to rage. The word is a bit literary; many people would just say annoy or bother. You will also meet irksome, the adjective, meaning “annoying.” Though actually, this word is an old cousin of work: it came from Old Norse yrkja, “to work,” and long ago it was about growing tired from labour. The meaning slid from “wear out” to “get on your nerves.”