Meaning

noun an informal term for a father; probably derived from baby talk

noun a sweet drink containing carbonated water and flavoring

noun a sharp explosive sound as from a gunshot or drawing a cork

originFrom Middle English pop, poppe (“a blow; strike; buffet”) (> Middle English poppen (“to strike; thrust”, verb)), of onomatopoeic origin – used to describe the sound, or short, sharp actions. The physics sense is part of a facetious sequence "snap, crackle, pop", after the mascots of Rice Krispies cereal.

Etymology from Wiktionary, CC BY-SA 3.0