Conscious thought male expressed (8)
I believe the answer is:
sentient
'conscious' is the definition.
(I've seen this before)
'thought male expressed' is the wordplay.
'thought' becomes 'sentiment' ('sentiment' can be a synonym of 'thought').
'male' becomes 'm' (common abbreviation).
'expressed' indicates named letters should be taken away (express can mean to squeeze out).
'sentiment' with 'm' taken away is 'SENTIENT'.
(Other definitions for sentient that I've seen before include "Able to perceive or feel things" , "Capable of feeling things as in tenets" , "Conscious - aware" , "Having feelings" , "Feeling, conscious" .)