• КАК ШТЫК прийти, явиться, быть и т.п. coll
[как + NP; nom only; subj-compl with copula (subj: human) or adv]
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⇒ (to come to, appear at some place) unfailingly and at the appointed time (if the time is indicated or implied):
- (on time and) without fail;
- [with the focus on the exact time] on the dot (on the nose, on the button).
♦ "Зачем тебе отпуск?" - спросил Андриолли. "К матери надо съездить, крышу покрыть. Пишет: текёт [ungrammat = течёт] крыша-то. На недельку, Матвей Матвеич. В тот понедельник как штык на работе буду", - заверил он в слабой надежде (Войнович 5). "What do you need leave for?" asked Andriolli. "I've got to go to my mother's and mend the roof. She wrote and told me it's leaking. Just for a week, Matvei Matveevich. I'll be back on the job next Monday. On the dot," he assured the director without much hope (5a).
Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. С.И. Лубенская. 2004.