Definition of cwm in English:



  • (especially in Wales) a steep-sided hollow at the head of a valley or on a mountainside; a cirque.

    in place names ‘there is a dusting of snow in Cwm Glas Mawr’
    • ‘The last snow shone on the slopes of the Brecon Beacons: pure white on the peaks and in the cwms, grey and stratified on the windward faces.’
    • ‘The Everest greenschists are thickest on the SW face of Everest and across the western cwm on Lhotse.’
    • ‘Apart from the cwm, Cader Idris shows many other features such as striations and moraines, as described in this University of Aberystwyth fieldwork leaflet, that clinch the identification of glacial origins.’
    • ‘Three prominent thin bands of pale-coloured calc-silicate marbles occur on the Lhotse face in the western cwm on the north face of Lhotse and high on the south face of the Lhotse-Nuptse ridge.’
    • ‘Perhaps just a tiny ridge of rock high in the snow-choked cwm.’


Mid 19th century: Welsh; related to combe.