Aware of a mawkishness Miles ignored (8)
I believe the answer is:
sentient
'aware' is the definition.
(I've seen this before)
'a mawkishness miles ignored' is the wordplay.
'a mawkishness' becomes 'sentiment' (I've seen this before).
'miles' becomes 'm' (common abbreviation).
'ignored' indicates named letters should be taken away.
'sentiment' with 'm' taken out is 'SENTIENT'.
'of' acts as a link.
(Other definitions for sentient that I've seen before include "Capable of feeling and perceiving things" , "Feeling, conscious" , "Able to perceive or feel things" , "Having feelings" , "Endowed with feeling and consciousness" .)