Irascible and wish to catch a snake! (7)
I believe the answer is:
waspish
'irascible' is the definition.
(I've seen this before)
'wish to catch a snake' is the wordplay.
'to catch' means one lot of letters goes inside another.
'a snake' becomes 'asp' (asp is a kind of snake).
'wish' placed around 'asp' is 'WASPISH'.
'and' is the link.
(Other definitions for waspish that I've seen before include "Easily-provoked" , "irascible" , "'Very irritable, like a stinger (7)'" , "Spiteful (with a slender waist?)" , "Easily angered - with black and yellow stripes?" .)