Like "they gon' catch up" fuck what you must heard!

from Joey BADA$$ (Ft. CJ Fly) – Hardknock Lyrics on Rap Genius

Meaning

A play on words. “Catch up” sounds like “ketchup” and “Must heard” sounds like “mustard”

Ketchup and mustard puns are quite common in rap One example comes from an unknown featuring artist on Drake’s “Belly Shit”:

They must heard that they’ll never catch up

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