He pretended that he had forgotten it: (S, KL, * TA:) and (TA) he forgot it; (MA, KL, * TA;) like ↓نَسِيَهُ: (TA:) [or] he constrained himself to dismiss it from his mind. (MA.)
2.
تُنُوسِىَIt (a word or the like) was forgotten by degrees. (Occurring often in the larger Lexicons.)