Subject to strong or violent sallies of imagination or excitement, which in some measure pervert the judgment and cause the person to act in a manner different from the more rational part of mankind; wild and erratic; partially mad. [It has been sometimes written phrentic, but is now generally written frantic.]

A person who is wild and erratic in his imagination.

Alt. of Phrenetical

One who is phrenetic.

Relating to phrenitis; suffering from frenzy; delirious; mad; frantic; frenetic.