Wagered (7)
'wagered' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for gambled that I've seen before include "Speculated - took chances" , "Took a chance" , "Took a punt" , "Wagered" , "Made a bet" .)
'wagered' is the definition.
(staking is a kind of wagering)
This is all the clue.
(Other definitions for staked that I've seen before include "Put down for bet" , "laid" , "Wagered or risked" , "Wagered with sharp sticks? (6)" , "Made bet or pierced with stick" .)