Minor act ridiculously sentimental (8)
I believe the answer is:
romantic
'sentimental' is the definition.
(I've seen this before)
'minor act ridiculously' is the wordplay.
'ridiculously' indicates an anagram.
'minor'+'act'='minoract'
'minoract' with letters rearranged gives 'ROMANTIC'.
(Other definitions for romantic that I've seen before include "Literary period in early 19th century" , "Coin mart (anag.)" , "Sentimental" , "Involving a love affair, appealing to the tender emotions" , "Evoking love; post-Classical" .)