Spotted pattern is deep (6)
I believe the answer is:
espied
'spotted' is the definition.
('espy' can be a synonym of 'spot')
'pattern is deep' is the wordplay.
'pattern' indicates an anagram (I've seen 'patterned' mean this (arranged following a pattern)).
'is'+'deep'='isdeep'
'isdeep' with letters rearranged gives 'ESPIED'.
(Other definitions for espied that I've seen before include "Watched" , "Saw (archaic)" , "Glimpsed" , "Caught sight of (poetic)" , "Caught sight of (archaic)" .)