Survey of English Place-Names

Etymology

Marishes parish includes a great part of the very low-lying land in the south of the wapentake and takes its name from the extensive marshes which it embraced till the land was drained.v. mersc . These probably included Aschilesmares , Aschelesmere 1086 DB (from ON  Áskell ), Chiluesmares , Chiluesmarsc 1086 DB, Kilverdesmersh 1152–6 Riev, Culverthesmersch 1160 Riev (cf. Killerby 103infra ), Maxudesmares , Maxudesmersc 1086 DB (first elements possibly being, as suggested by Dr Lindkvist, the ON  pers. n. Mákr (LindN) and wudu ), Odulfesmare , Ouduluesmersc (from ON Auðulfr ) and Theokemarais 1189 Riev, 1252 Ch, -mar 1201 ChR, in which the first element is perhaps an unrecorded ON  by-name Þjokka (gen. Þjokku ) 'thick'; v. LindBN s.n.Þjokkubeinn 'thick leg.' The suffix in some of these forms has been influenced by OFr  marais .