Picasso finds second bunk unusually roomy (8)
I believe the answer is:
spacious
'roomy' is the definition.
(I know that roomy can be written as spacious)
'picasso finds second bunk unusually' is the wordplay.
'finds' says to put letters next to each other.
'second bunk' becomes 'u' (2nd letter of 'bunk').
'unusually' indicates anagramming the letters.
'picasso'+'u'='picassou'
'picassou' with letters rearranged gives 'SPACIOUS'.
(Other definitions for spacious that I've seen before include "wide-ranging" , "Big and roomy" , "Having plenty of room" , "Roomy, not congested" , "Ample, roomy" .)