[VP; subj: human; if the obj is a count noun, it is usu. pi]
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⇒ to have an understanding of some group of people or type of person; to be extremely knowledgeable in some area, field etc:
- X знает толк в Y-ax (Y-e) ≈ X knows what's what in (when it comes to) Y;
- X knows all there is to know about Y;
- X knows all about Ys;
- [in limited contexts] X is a connoisseur (a good judge) of thing Y.
♦ Ты гурман. Ты знаешь толк в еде и в винах... (Аксёнов 2). You're an epicure. You know what's what in food, and in wines... (2a).
♦ ...[Арина Власьевна] в хозяйстве, сушенье и варенье знала толк... (Тургенев 2). ...[Arina Vlas'evna] knew all there was to know about housekeeping and the drying and preserving of fruit... (2e).
♦ У другого, помоложе, розоватое лицо человека, который понимает толк в винах (Булгаков 5). The other man, younger, has the rosy face of a connoisseur of wines (5a).
♦ Эта Муся Борисовна никому ничего не жалела... ее считали святой, старухи, знавшие толк в людях, целовали ей платье (Гроссман 2). She [Musya Borisovna] never grudged anyone any thing. ... She had been looked on as a saint; the old women, good judges of character, used to kiss her dress (2a).
Большой русско-английский фразеологический словарь. — М.: ACT-ПРЕСС КНИГА. С.И. Лубенская. 2004.