What does ha! mean in Latin?

ha!, a interjection, means “thank heavens!”.

interjection

ha!¹

ha! interj.

I. Ha hae or hahae, an exclamation of joy, thank heavens! hahae, nunc demum mi animus in tuto locost, Plaut. Ps. 4, 5, 1.—

II. Ha ha he, or in one word, hahahe, an exclamation of laughter or derision, ha! ha! ha! Chr. Ha, ha, he! Me. Quid risisti? Ter. Heaut. 5, 1, 13; Plaut. Ps. 4, 1, 36; Ter. And. 4, 4, 15; id. Eun. 3, 1, 36; 3, 2, 44; id. Hec. 5, 4, 22; id. Phorm. 2, 3, 64: hahahe, jam teneo, quid sit, Plaut. Poen. 3, 5, 23.

noun · neuter

hā²

hā n or f (indeclinable)

Classical[ˈhaː]Ecclesiastical[ˈaː]

interjection

ha³

Classical[ˈha]Ecclesiastical[ˈaː]

Onomatopoeic.