Smiled when a spider got me agitated (8)
I believe the answer is:
simpered
'smiled' is the definition.
(simpering is a kind of smiling)
'a spider got me agitated' is the wordplay.
'got' means one lot of letters go next to another.
'agitated' indicates an anagram.
'spider'+'me'='spiderme'
'spiderme' is an anagram of 'SIMPERED'.
'when' is the link.
(Other definitions for simpered that I've seen before include "Smiled in affected way" , "made with mince" , "Smiled stupidly" .)