Tigrinya

fäṭänä - to be rapid (TED 2732)

PES
*fṭn - to be fast (CDG 171; Kogan 2015: 459)
The origin of Proto-EthS *fṭn ‘to be fast’ is uncertain, but Leslau may be right to connect it with Arb. fṭn ‘to be intelligent, sagacious’ (Lane 2418).