Akademik

по ноге
ПО НОГЕ{{}}
[PrepP; Invar; subj-compl with copula (subj: a noun denoting footwear) or nonagreeing modif]
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of the correct size, comfortable on s.o.'s feet:
- X Y-y по ноге{{}} X is the right <my, your etc> size;
- X fits (well);
|| Neg X Y-у не по ноге{{}} X doesn't fit (right);
- X is too big (small, tight) for Y.
     ♦ ...Семнадцатую путёвку принесла женщина в ватной солдатской теплушке, в больших, не по ноге, сапогах (Шолохов 3). A seventeenth warrant was brought by a woman in a soldier's wadded jacket and boots that were too big for her (3a).

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