The French kiss is rather sloppy (3)
I believe the answer is:
lax
'rather sloppy' is the definition.
'lax' can be an answer for 'sloppy' (both can careless). I'm not sure about the 'rather' bit.
'the french kiss' is the wordplay.
'the french' becomes 'la' ('the' in French).
'kiss' becomes 'x' (X can represent a kiss).
'la'+'x'='LAX'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for lax that I've seen before include "without tension" , "Not taut" , "Not sufficiently strict" , "Loose or immoral" , "Flabby" .)