Sentence:  His energy was prodigious ; sometimes he would be up before dawn , clad as a garbage collector and hurling pails into areaways to exasperate us , and thereafter would hurry to the Bronx Zoo to <WSD>grimace</WSD> at the lions and press cigar butts against their paws . 
Meaning of the word marked with <WSD> tags:  contort the face to indicate a certain mental or emotional state