Green around the gills is an idiom that is used to describe someone who looks pale and unwell. It is derived from the phrase 'green around the gills, ' which refers to the greenish hue of a person's skin when they are ILL or nauseous. The crossword solutions for this term are ILL (3 letters) and SICK (4 letters). Both words refer to a person's physical state of being unwell, which is the meaning behind the phrase 'green around the gills.'