Lewis Short
(adjective) : văpĭdus, a, um, vapor
* That has emitted steam or vapor, i. e. that has lost its life and spirit, spoiled, flat, vapid.
* Lit.: vinum,Col. 12, 5, 1.
* Transf., spoiled, bad.
* Lit.: pix,Pers. 5, 148.
* Trop.: astutam vapido servas sub pectore vulpem,Pers. 5, 117.—Adv.: văpĭdē, poorly, badly, ill: se habere, for male se habere, a favorite expression of Augustus,Suet. Aug. 87.
Charlton T. Lewis, Charles Short, A Latin Dictionary