Lewis Short
lentĭtūdo (noun F) : id.
* Slowness, sluggishness, inactivity.
* Lit.: conjuratorum,Tac. A. 15, 51; Vell. 2, 11, 2.
* Trop.: dulness, apathy, insensibility, Cic. Tusc. 4, 19, 43: omnino non irasci est non solum gravitatis, sed nonnumquam etiam lentitudinis,id. Q. Fr. 1, 1, 13, § 38.—Of speech: libros ejusdem lentitudinis ac teporis,dulness, heaviness,Tac. Or. 21, 6.
Charlton T. Lewis, Charles Short, A Latin Dictionary