Wiktionary
take a stab at
vb. 1 (context idiomatic English) To attempt or try. 2 (context idiomatic English) To guess.
Usage examples of "take a stab at".
Are there any liberals in the back rows who want to take a stab at answering this one?
No telling how long we'll fiddle around out there before we take a stab at it.
Try dividing the Federal Budget by the number of wage earners not on the public payroll, then take a stab at where you fit in.