The term 'JUST SITTING' can be broken down into three crossword solutions: INERT (5 letters), IDLE (4 letters), and UHFX (4 letters). INERT is an adjective meaning 'inactive, sluggish, or unmoving'. IDLE is also an adjective meaning 'not working or productive'. UHFX is an acronym for 'Unemployed, Homeless, and Financially Excluded', which is a term used to describe people who are not employed, have no home, and lack access to financial services. All three terms refer to the same concept of being inactive or not working.