The term 'EXTREMELY UNPLEASANT' can be described by the crossword solutions of VILE (4 letters), NASTY (5 letters), and MESSY (5 letters). These words all describe something that is unpleasant, but to a greater degree. VILE is an adjective used to describe something that is morally reprehensible or disgusting. NASTY is an adjective used to describe something that is unpleasant, offensive, or disgusting. MESSY is an adjective used to describe something that is untidy, disorganized, or chaotic. All three words together paint a picture of something that is extremely unpleasant.