Fluish feeling is a term used to describe a general feeling of discomfort and unease. It can be caused by a variety of illnesses, such as the flu or a cold. The two crossword solutions for this term are ACHE and AGUE, both of which are four letters long. ACHE is a verb meaning to have a dull, continuous pain, while AGUE is a noun meaning a fever or chill, usually associated with malaria. Both of these words can be used to describe the fluish feeling that one may experience when they are ill.