Old bed accommodating the Spanish cat (6)
I believe the answer is:
ocelot
'cat' is the definition.
(ocelot is a kind of cat)
'old bed accommodating the spanish' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'bed' becomes 'cot' (cot is a kind of bed).
'accommodating' indicates putting letters inside.
'the spanish' becomes 'el'.
'cot' enclosing 'el' is 'celot'.
'o'+'celot'='OCELOT'
(Other definitions for ocelot that I've seen before include "Feline of South and Central America" , "Fur" , "Big cat" , "Nocturnal wild cat of Central and South America" , "Animal in the loo etc." .)