† grievoustyObs. In 5 grevouste, -osetee. [f. grievous + -ty.] Grievousness, heinousness. c1410Love Bonavent. Mirr. xxxiv. 68 (Gibbs MS.) Also to schewe þe greuouste of synn in custome.c1425Orolog. Sapient. ii. in Anglia X. 342/38 Þou schalt gretelye weye þe grevosetee of þine sinnes.