The term 'more furtive' can be described by five different crossword solutions: slier (5 letters), slyer (5 letters), shiftier (8 letters), slinkier (8 letters), and SNEAKIER (8 letters). Slier and slyer both refer to someone who is crafty or cunning, while shiftier and slinkier both refer to someone who is sly and stealthy. Finally, SNEAKIER refers to someone who is sly and secretive. All of these words describe someone who is more furtive than the average person.