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Webster 1913 Edition
Petulant
Pet′u-lant
,Adj.
 [L. 
petulans
, -antis
, prop., making slight attacks upon, from a lost dim. of petere 
to fall upon, to attack: cf. F. pétulant
. See Petition
.] 1. 
Forward; pert; insolent; wanton. 
[Obs.] 
Burton.
 2. 
Capriciously fretful; characterized by ill-natured freakishness; irritable. 
“Petulant moods.” Macaulay.
 
Syn. – Irritable; ill-humored; peevish; cross; fretful; querulous. 
Webster 1828 Edition
Petulant
PET'ULANT
,Adj.
 1.
  Manifesting petulance; proceeding from pettishness; as a petulant demand; a petulant answer.2.
  Wanton; freakish in passion.