sing-song
sing-song ▶adjective (of a person's voice ) having a repeated rising and falling rhythm: the sing-song voices of children reciting tables. ▶noun 1 Brit. informal an informal gathering for singing. 2 [ in sing. ] a sing-song way of speaking. ▶verb ( sing-songs, sing-songing, sing-songed ) [ no obj. ] speak or recite something in a sing-song manner.
sing-song adjective he began to recite in a sing-song voice: chanting, chant-like; monotonous, monotone, droning, toneless.