from
The Collaborative International Dictionary of English v.0.48
Frounce \Frounce\, v. i. [imp. & p. p. {Frounced}; p. pr. & vb.
n. {Frouncing}.] [OE. frouncen, fronsen, to told, wrinkle,
OF. froncier, F. froncer, perh. fr. an assumed LL. frontiare
to wrinkle the forehead, L. frons forehead. See {Front}, and
cf. {Flounce} part of a dress.]
To gather into or adorn with plaits, as a dress; to form
wrinkles in or upon; to curl or frizzle, as the hair.
[1913 Webster]
Not tricked and frounced, as she was wont. --Milton.
[1913 Webster]