Three words: syncopation, fermatas, and pickups
(or "pickup notes" ...but that still counts as one word!)
Based on just humming the tune in my head, I'm pretty sure it's mostly in 4/4, but I'll happily do a transcription to confirm this when I get near a recording. But basically there's a ton of syncopation (displaced accents), fermatas (pauses where notes and/or rests are held beyond their metric value because "time stops" [sic]), and pickup notes...e.g., those three notes at the beginning of every verse riff are pickups, and then the fourth note is the downbeat.