'vocabulary-wise' originates from Modern English, formed by combining 'vocabulary' (from Latin 'vocabulum') and the suffix '-wise' (from Old English 'wīse'), where 'vocabul-' meant 'word' and 'wīse' meant 'manner' or 'way'.

'vocabulary' changed from Late Latin 'vocabularium' and Middle French 'vocabulaire' and eventually became the modern English word 'vocabulary'; the suffix '-wise' developed from Old English 'wīse' to Middle English '-wise' and became the modern English suffix used to mean 'in the manner of' or 'with respect to'.

Initially the compound would literally mean 'in the manner of vocabulary,' but over time it evolved into the idiomatic modern sense 'with respect to vocabulary'.