ONlwSG

²plod m. [pʰɫ̪ɔd̪̥], gen. ploda -[ə] and pluid [pʰɫ̪ud̥ʲ], ‘pool (of standing water)’. McDonald (2009, 354) proposes a derivation for Ir., SG and Mx plod ‘a pool, standing water’ and SG flod ‘idem’ from ON flóð nt. ‘a flood, inundation, deluge; tidal flow; a flood, river or sea’ (after Cleasby 1874) on the basis of the plod ~ flod variation in Scottish Gaelic, but concludes on semantic grounds that the Old Norse derivation is unlikely. At any rate, Old Norse long ó would not normally be expected to yield short o in Gaelic; the Old Norse fricative ð would not normally be expected to yield a plosive in Gaelic (Cox 2007b); and SG flod in the sense ‘pool’ is unattested. McDonald notes MacBain’s (1911) derivation from MEng. plod(de) (plud(de)) ‘a puddle’ (cf. OED^˄, s.v. plud: Ir. and SG plod ‘are probably < English’), and this seems probable.

For the diminutive SG plodan ‘small pool’, cf. Ir. plodán ‘stagnant pool; puddle’ and plodar ‘miry place, slough’ (see below).

For Ir. plod, 

Cf. Lhuyd 1707: ‘plod & plodán “standing water” ’.

cf. Ir. ploda ~ pluda ‘mud, slush’. The diminutive and derivative forms Ir. plodán and plodar are treated as variants of Ir. lodán and lodar, respectively (Ó Dónaill 1977), cf. SG lod and lodan ‘idem’ (EG lodán, which MacBain (1911) sees as cognate with Lat. lŭtum ‘mud’).

Mx plod appears to occur only in Y Kelly’s (1866) dictionary, where it may have been adopted from Irish, cf. ibid.: ‘plodan “a small pool” (Ir. plodan [sic])’.