n. 25B6; noun
much to his annoyance, Louise didn't even notice : IRRITATION, exasperation, vexation, indignation, anger, displeasure, chagrin; informal aggravation.
they found him an annoyance : NUISANCE, pest, bother, irritant, inconvenience, thorn in one's flesh; informal pain (in the neck), bind, bore, hassle; N. Amer. informal nudnik, burr in/under someone's saddle; Austral./NZ informal nark.