"U not my dad" is used as a reply when someone who isn't a family member (specifically your dad) tells you to do something and you reply with, "you not my dad".
Step dad: "austin pick that shit up"
Austin : "u not my dad u always tryna say something fuckn stupid ass noodle head"
Austin : "u not my dad u always tryna say something fuckn stupid ass noodle head"
by Unotmydad69 January 22, 2016
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