Assorted male cousins unexpectedly entertaining the Spanish (13)
I believe the answer is:
miscellaneous
'assorted' is the definition.
(I know that assorted can be written as miscellaneous)
'male cousins unexpectedly entertaining the spanish' is the wordplay.
'unexpectedly' is an anagram indicator.
'entertaining' is an insertion indicator (inviting in, as for dinner).
'the spanish' becomes 'el' ('the' in Spanish).
'male'+'cousins'='malecousins'
'malecousins' is an anagram of 'misclaneous'.
'misclaneous' placed around 'el' is 'MISCELLANEOUS'.
(Other definitions for miscellaneous that I've seen before include "Mixed, varied" , "Assorted" , "Of various types" , "Multifarious" , "Not just one kind" .)