The term GREEN GROUP is composed of two crossword solutions, AMATEURS and REM. AMATEURS is an 8-letter word meaning 'people who engage in an activity for pleasure rather than for financial benefit or professional reasons'. REM is a 3-letter word meaning 'rapid eye movement', which is a stage of sleep characterized by rapid movement of the eyes. Together, these two words form the phrase GREEN GROUP, which could refer to a group of people who are passionate about environmentalism or sustainability.