'abomasum' originates from New Latin, specifically the word 'abomasus,' where 'ab-' meant 'away from' and 'omasus' referred to 'the third stomach of a ruminant.'

'abomasus' transformed into the modern English word 'abomasum' through scientific Latin usage.

Initially, it referred specifically to the fourth stomach of ruminants, and this meaning has remained consistent in modern usage.