Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.
Class II. Words Relating to SpaceSection III. Form
3. Superficial Form
252. Concavity.
EXCAVATION, pit, sap, mine, shaft, colliery; caisson, fougasse [F.], countermine; trough (furrow) [See Furrow]; bay &c. (of the sea) [See Gulf; Lake].
cup, basin, crater, punch bowl; cell (receptacle) [See Receptacle]; socket.
VALLEY, vale, dale, dell, dingle, coomb or combe, bottom, slade [obs.], strath [Scot.], gill or ghyll [Scot. & dial. Eng.], glade, grove, glen, donga [S. Africa], nullah [India], park [U. S.].
CAVE, subterrane, cavern, cove; grot, grotto; alcove, blind alley, cul-de-sac [F.], hole, burrow, kennel, tunnel; gully [See Interval]; arch (curve) [See Curvature].
EXCAVATOR, sapper, miner.
RENDER CONCAVE &c. adj.; depress, dish, hollow; scoop, scoop out; gouge, dig, delve, excavate, dent, dint, mine, sap, undermine, burrow, tunnel, stave in.