know your onions
US /noʊ jʊər ˈʌnjənz/
UK /noʊ jʊər ˈʌnjənz/
1.
saber mucho, ser un experto
to be very knowledgeable about a particular subject or field
:
•
You can trust her advice; she really knows her onions when it comes to finance.
Puedes confiar en su consejo; ella realmente sabe mucho de finanzas.
•
The mechanic quickly identified the problem, proving he really knew his onions.
El mecánico identificó rápidamente el problema, demostrando que realmente sabía mucho.