On such trips I included a pillow (7)
I believe the answer is:
cushion
'a pillow' is the definition.
(I've seen this before)
'on such trips i included' is the wordplay.
'trips' indicates an anagram.
'included' means one lot of letters goes inside another.
'on'+'such'='onsuch'
'onsuch' with letters rearranged gives 'cushon'.
'cushon' enclosing 'i' is 'CUSHION'.
(Other definitions for cushion that I've seen before include "Protect from blow" , "Chair pad or pillow" , "See 9" , "Part of a billiard table" , "Soften (the effect of an impact)" .)