1) Abstract 2) Act the pickpocket 3) Cabbage 4) Exclusively Anglo word 5) Exclusively Saxon word 6) Hogwarts caretaker 7) Hook 8) Lift 9) Nobble 10) Pilfer 11) Pinch 12) Purloin 13) Rip off 14) Snarf 15) Sneak 16) Steal 17) Swipe 18) Take something the wrong way 19) Take the wrong way 20) To pilfer, to steal Found on https://www.crosswordclues.com/clue/filch
Filch (fĭlch) transitive verb [ imperfect & past participle Filched (fĭlcht); present participle & verbal noun Filching .] [ Confer Anglo-Saxon feolan to stick to, Old High German felhan , felahan , to ... Found on http://www.encyclo.co.uk/webster/F/28