TRIM:
Old English trymman,trymian 'make firm,arrange',of which the adjective appears to be a derivative.The word's history is obscure; current verb senses date from the early 16th cent.when usage became frequent and served many purposes:this is possibly explained by spoken or dialect use in the Middle English period not recorded in extant literature
SLUM:
early 19th cent.(originally slang,in the sense 'room'):of unknown origin
MASK:
mid 16th cent.:from French masque,from Italian maschera,mascara,probably from medieval Latin masca 'witch,spectre',but influenced by Arabic masḵara 'buffoon'
SEW:
Old English siwan,of Germanic origin,from an Indo-European root shared by Latin suere and Greek suein
EBB:
Old English ebba (noun),ebbian (verb),of West Germanic origin; related to Dutch ebbe (noun),ebben (verb),and ultimately to of which had the primary sense 'away from'