'thiazole' originates from 'International Scientific Vocabulary', specifically the combination of 'thio-' meaning 'sulfur' and 'azole' (a class of five-membered nitrogen-containing heterocycles).

'thiazole' was coined in the late 19th century as chemists began to systematically name new heterocyclic compounds, and it became the modern English word 'thiazole'.

Initially, it meant 'a five-membered ring containing both sulfur and nitrogen', and this meaning has remained consistent in modern usage.