в соку

• В (САМОМ <ПОЛНОМ> СОКУ coll

[PrepP; these forms only; subj-compl with быть (subj: human) or nonagreeing modif]

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⇒ one is at the point in life when one's health and vigor are at their peak:

- in the prime of (one's) life;

- in one's prime.

     ♦ "Да кто же мужчины носят корсет? - возражала Варвара, - никто не носит". - "Верига носит", - сказал Передонов. "Так Верига - старик, а ты, Ардальон Борисыч, слава богу, мужчина в соку" (Сологуб 1). "Whoever heard of a man wearing a corset," retorted Varvara. "No one wears one." "Veriga does," said Peredonov. "But Veriga's an old man, while you, Ardal'on Borisych, are thank God, in the prime of life" (1a).