ONSET
Meaning of ONSET in English
/ ˈɒnset; NAmE ˈɑːn-; ˈɔːn-/ noun
[ sing. ] the beginning of sth, especially sth unpleasant :
the onset of disease / old age / winter
Oxford Advanced Learner's English Dictionary.
Оксфордский английский словарь для изучающик язык на продвинутом уровне.
2005