Someone’s strong suit is an attribute, field of work, or set of skills that they thrive in.
Saying something is a person’s strong suit is exclusively a positive thing to say, and is usually used to evaluate the excellence of individuals.
In the card games bridge and whist, strong suit is a situation where you’re holding a number of high cards of one suit in a hand.
As mentioned above, the expression is used in card games in a literal sense. The phrase was initially recorded some time during the early to mid-1860s.
It is believed that the term’s more abstract meaning derived directly from there.
The expression is very commonly used both in spoken and written English around the globe. One of the more recognized idioms.
Strong suit is used in professional environments especially frequently.