Answer:

fossil

AnswerCrossword Clue
FOSSILWhat's left of a dinosaur
FOSSILWhat each circled square in this puzzle represents
FOSSILBone to pick?
FOSSILOld fogy
FOSSILHas-been
FOSSILDinosaur remnant
FOSSILOld-fashioned one
FOSSILThing of the past