simper
To smile in a foolish, frivolous, self-conscious, coy, obsequious, or smug manner.
intransitive
How the fools kotowed and simpered while I looked over their jewels and speculated upon how much I could get for them!
To glimmer; to twinkle.
obsolete
Yet can I mark how stars above / Simper and shine.
Where it comes from
Uncertain; compare (probably from) Danish simper / semper (“coy”), German zimper (“elegant, dainty”).
Adapted from the Wiktionary entry simper (CC BY-SA 4.0).