1996: cesspool Jun 2, 2020

A cesspool is not a pool of 'cess', though in Irish it is another term for taxes, and no one likes those either. Rather, looking at its older form 'suspiral', which denoted an air vent or water pipe, this is all derived from the Old French 'souspirail' from the Latin 'sub-' (‘from below’) and 'spirare' meaning ‘to breathe’. However, by at least the 17th century, the spelling had changed with association to the word 'pool', and 'cess' took on a meaning of its own, probably related to sewage, as can be seen also in 'cesspit'. Moreover, since it denotes an underground container for sewage, it has lost the relation to air anyway.
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