10th cent. Old Spanish fambre, earlier famne. The n in famne was tapped by the tongue and became *famre. *b intervenes between *mr via epenthesis to become fambre. From Vulgar Latin *famine 'id.,' earlier famis, from Latin fames 'id.'
Of unknown origin. A connection to *dhH- "to disappear" has been proposed, albeit with its own problems. See Walde & Hoffman (1954) for further discussion.
Western Vulgar Latin: Asturian fame, Portuguese fome, Galician fame, Catalan fam, French faim, Italian fame; Eastern Vulgar Latin: Aromanian foami, Romanian foame; Sardinian: fàmene
In the 3rd or 4th cent. text Appendix Probi we find the line: fames non famis "[the word for 'hunger' is] fames, not famis." The author's spelling correction proves how the word was pronounced by common speakers, and offers a rare glimpse of the evolution of Latin into Romance languages such as Spanish.
Words for hunger tended to be borrowed into Indo-European languages or internally innovated. "There is only one word reconstructed in Proto-Indo-European that means 'hunger' (a Hittite-Tocharian isogloss) and even this is problematic in tha a comparison between Hit kāst- 'hunger' and Toch B kest 'hunger' still only yields a PIE *Kos-t-, i.e. we can only say that the word begins with a velar but must be uncertain which velar that is (it could be *ges- for example)." ~ Mallory & Adams, The Oxford Introduction to Proto-Indo-European and the Proto-Indo-European World (2006)