Chose quiet time to probe dictionary (5)
I believe the answer is:
opted
'chose' is the definition.
(to opt for something is to choose it)
'quiet time to probe dictionary' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'time' becomes 't' (abbreviation).
'to probe' indicates putting letters inside (probe can mean to poke or prod into).
'dictionary' becomes 'OED' (Oxford English Dictionary).
'p'+'t'='pt'
'pt' put into 'oed' is 'OPTED'.
(Other definitions for opted that I've seen before include "Chose from depot" , "Plumped (for)" , "Chosen - elected" , "Depot (anag.)" , "Made choice, selected" .)