moved to or showing sudden, impatient irritation, especially over some trifling annoyance
1599, "immodest, wanton, saucy," from M.Fr. petulant (1350), from L. petulantem (nom. petulans) "wanton, froward, insolent," from the root of petere "rush at, seek" (see petition). Meaning "peevish, irritable" first recorded 1775, probably by influence of pet (2).
"Later, like a petulant artist, he insisted that his signature be an incomprehensible glyph".
- Charles Mann, 1493: Uncovering the New World Columbus Created