crackers

(noun) a thin crisp wafer made of flour and water with or without leavening and shortening; unsweetened or semisweet. Synonyms: cracker.

(noun) a poor White person in the southern United States. Synonyms: redneck, cracker.

(noun) a programmer who cracks (gains unauthorized access to) computers, typically to do malicious things. Synonyms: cracker. Examples: "Crackers are often mistakenly called hackers."

(noun) firework consisting of a small explosive charge and fuse in a heavy paper casing. Synonyms: firecracker, cracker, banger.

(noun) a party favor consisting of a paper roll (usually containing candy or a small favor) that pops when pulled at both ends. Synonyms: cracker, snapper, cracker bonbon.

(adj) informal or slang terms for mentally irregular. Synonyms: balmy, barmy, bats, batty, bonkers, buggy, cracked, daft, dotty, fruity, haywire, kooky, kookie, loco, loony, loopy, nuts, nutty, round the bend, around the bend, wacky, whacky. Examples: "It used to drive my husband balmy."