Akademik

ничего во рту не было
• МАКОВОЙ РОСИНКИ <НИ (МАКОВОЙ) РОСИНКИ, НИЧЕГО> ВО РТУ НЕ БЫЛО (у кого) coll
[VPsubj/ gen; past only]
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⇒ s.o. has not eaten anything at all:
- у X-a маковой росинки во рту не было{{}}≈ X hasn't had (touched, eaten) a thing;
- X hasn't eaten a bite (a scrap of food);
- X hasn't had a (single) bite (to eat);
- X hasn't had a morsel of food;
- X has had nothing whatsoever.
     ♦ "Я измучена, даже есть не могу, хотя с утра во рту ни маковой росинки" (Свирский 1). "I'm exhausted, I can't swallow a thing, although I haven't eaten a scrap of food all day" (1a)
     ♦ [Астров:] Возился я целый день, не присел, маковой росинки во рту не было... (Чехов 3). [А ] I was on the go all day - didn't so much as sit down or have a bite to eat... (Зс) [A. ] I was on the move all day, didn't sit down or have a morsel of food... (3a).
     ♦ ...Семен, разбудив старуху, наскоро перекусил - больше суток маковой росинки не было во рту... (Тендряков 1). Simon woke up his wife and had a bite to eat-he had had nothing whatsoever for more than twenty-four hours... (1a)

Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. . 2004.