The only free and comprehensive online etymological dictionary of the Spanish language
octubre m. (Noun) "October"
13th cent. From Latin octubrem, accusative of october 'id.,' from octo "eight" (see ocho) and a suffix -ember created by analogy with september "September" (see septiembre).
Indo-European
Romance
Asturian ochobre, Galician outubro, Portuguese outubro, Catalan octubre, French octobre, Italian ottobre, Romanian octombrie