Lewis Short
nĭtēla (noun F) : niteo
* Brightness, splendor (post-class.).
* Lit.: armorum nitela,Sol. 22, 5.
* Transf.
* That which shines or glitters, a glittering particle: nitelae pulveris,gold-dust,Sol. 23, 4.
* That which causes to shine, a polish: nitelae oris, i. e. tooth-powder, Cat ap. App. Mag. p. 277, 5.
Charlton T. Lewis, Charles Short, A Latin Dictionary