Celtic centre occasionally starts to recruit artists and the like (2,6)
I believe the answer is:
et cetera
'and the like' is the definition.
(thesaurus)
'celtic centre occasionally starts to recruit artists' is the wordplay.
'occasionally' means one should take alternating letters.
'starts to' says to take the initial letters.
The initial letters of 'recruit artists' is 'ra'.
'celtic'+'centre'='celticcentre'
The alternate letters of 'celticcentre' are 'etcete'.
'etcete'+'ra'='ET CETERA'
(Other definitions for et cetera that I've seen before include "and the like" , "Drive out, expel" , "That can reduce length of sentence" , "that reduces length of sentence" , "something similar" .)