fucklehead Share definition Flag Lit., "fucking knucklehead" Usually reserved for someone who stubbornly adheres to false principles or consistently acts irresponsibly; generally, an idiot. "She hates your guts, you fucklehead! Quit calling her!" fucklehead by Darhug April 9, 2009 Words you can keep railfan mug chonk mug chud mug based mug 67 mug slime mug mogging mug chopped mug thot mug glazing mug huzz mug yams mug larp mug unc mug cracked mug simp mug baddie mug bop mug lolcow mug