What does fatheaded mean?
Fatheaded is an informal adjective meaning stupid, foolish, or stubbornly lacking in good judgement. It belongs to a long English tradition of insults built on 'head' — alongside blockhead, thickhead, and hothead — in which the shape or contents of the head stand in for the quality of the mind. Calling a decision, plan, or person fatheaded signals exasperation more often than real hostility; it is the sort of word used in a sighing reprimand among colleagues or friends rather than in formal abuse. The hyphenated spelling 'fat-headed' is equally acceptable, particularly in British usage, and the related noun 'fathead' names the person directly. Because the word's meaning is transparent from its parts, it needs no explanation — which is precisely what makes it an efficient, mildly comic way to call something foolish without resorting to coarser language.
adjectiveStupid or foolish; characterised by a lack of good judgement or common sense. It is most often used as a mildly contemptuous insult, frequently in the fuller form 'fat-headed'.
- Stupid, foolish, or obstinately lacking in good judgement (used as an insult or dismissive criticism).
"It was a fatheaded decision to sell the shares the week before the merger was announced."
"Only someone truly fatheaded would leave the keys locked inside the car twice in one week."
""Don't be so fatheaded," she said, sliding the map back across the table."
It's one of the rare insults where the insult is literally spelled out: fat + head = stupid, a compound insult that's been doing honest work in English since the nineteenth century.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of fatheaded
Fatheaded is a transparent English compound of 'fat' and 'head', formed on the model of earlier head-based insults such as blockhead (attested from the sixteenth century). The noun 'fathead', meaning a stupid person, is attested from the mid-nineteenth century, and the adjective followed as a natural derivative. Similar formations appear across Germanic languages, where 'fat' or 'thick' plus 'head' has long served as a figure for dullness.
Related word forms
How fatheaded is actually used
Informal and mildly insulting rather than vitriolic; it carries a teasing or exasperated tone more often than genuine malice. The hyphenated form 'fat-headed' is at least as common as the solid form, especially in British English.
Easily confused with fatheaded
Hot-headed means impulsive and quick-tempered, whereas fatheaded means stupid or lacking sense.