1 grúfa
u, f., in the phrase, á grúfu, grovelling, face down, on one’s belly; symja á grúfu, to swim on one’s belly, Sks. 177, Eg. 107, Fms. vii. 250, Fas. iii. 573, N. G. L. i. 80, Stj. 435, v. l., Art. 73, opp. to opinn (mod. upp í lopt, face up); liggr á grúfu ok horfir upp nef, a riddle of a ‘ladle;’ opinn eða á grúfu, Karl. 259.
2 grúfa
2. [cp. gruvesten = hearth-stone, gruva = the hearth, chimney, and gruve-hynna = the chimney-corner, Ivar Aasen]: whence ös-grúi, an ash-pit, Fas. i. (in a verse).