fen¹ / fen/ • n. a low and marshy or frequently flooded area of land. ∎  (the Fens) flat low-lying areas of eastern England, formerly marshland but largely drained for agriculture since the 17th century. ∎ Ecol. wetland with alkaline, neutral, or only slightly acid peaty soil. Compare with bog.fen² • n. (pl. same) a monetary unit of China, equal to one hundredth of a yuan.

fen An area of wet peat that is typically alkaline in reaction, or sometimes neutral or only very slightly acidic. In Britain the characteristic fenland area is northern East Anglia, around the Wash. Alkalinity is due to groundwater draining from surrounding calcareous rocks. Compare bog.

fen An area of wet peat, but one that is typically alkaline in reaction, or sometimes neutral or very slightly acidic. In Britain the characteristic fenland area is northern East Anglia, around the Wash. Alkalinity is due to ground water draining from surrounding calcareous rocks. Compare BOG.

fen OE. fen(n) = OS. fen(n)i (Du. veen), OHG. fenna, fenni (G. fenn), ON. fen, Goth. fani :- Gmc. *fanjam *-jaz *-jō :- IE. *pano-, rel. to Skr. páṅka- mud, OPruss. pannean marsh.

fen See hydrosere.