Chokedamp is a compound of choke + damp, where damp here is an old miners' term for a noxious gas or vapor, from Middle Low German damp ('vapor, steam'). The historical trail runs through damp in Middle Low German. Morphologically, chokedamp is transparent: it is a compound of choke + damp, where damp here is an old miners' term for a noxious gas or vapor, from Middle Low German damp ('vapor, steam'). Used as a noun, chokedamp now means "suffocating carbon-dioxide-laden air in a mine", so the present definition can be read against the older forms and meanings. The same lexical family is also visible in related forms such as choke and damp. The modern word remains analyzable through its parts, which makes the semantic connection unusually direct.