Used to dig suit (6)
I believe the answer is:
spades
'used to dig suit' is the definition.
I can't tell whether this defines the answer.
'dig suit' is the wordplay.
'dig' becomes 'spade' (spading is a kind of digging).
'suit' becomes 's' (this might be a standard abbreviation I've not previously seen).
'spade'+'s'='SPADES'
Can you help me to learn more?
(Other definitions for spades that I've seen before include "Suit in pack of cards" , "dark suit" , "Digging tools and card suit" , "Card suit and sturdy shovels" , "those getting soiled?" .)