The definition of gravitas is seriousness, dignity and good behavior.
An example of gravitas is how a president acts when while giving a speech.
[often in italics] weight, as of a leader or official; dignity, seriousness, credibility, etc.
Origin of gravitasfrom L, literally , weight from gravis, heavy: see grave
Seriousness or solemnity in demeanor or treatment: a candidate who lacks gravitas; an article with sufficient gravitas to be compelling.
Origin of gravitasLatin gravitās heaviness, seriousness ; see gravity .
Frequently used in a jocular or stilted sense.
From Latin gravitās (“weight, heaviness”)