From The Collaborative International Dictionary of English v.0.48:
Pen \Pen\, v. t. [imp. & p. p. Penned; p. pr. & vb. n.
Penning.]
To write; to compose and commit to paper; to indite; to
compose; as, to pen a sonnet. "A prayer elaborately penned."
--Milton.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Pen \Pen\, v. t. [imp. & p. p. Pennedor Pent (?); p. pr. &
vb. n. Penning.] [OE. pennen, AS. pennan in on-pennan to
unfasten, prob. from the same source as pin, and orig.
meaning, to fasten with a peg.See Pin, n. & v.]
To shut up, as in a pen or cage; to confine in a small
inclosure or narrow space; to coop up, or shut in; to
inclose. "Away with her, and pen her up." --Shak.
[1913 Webster]
Watching where shepherds pen their flocks at eve.
--Milton.
[1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Penned \Penned\, a.
1. Winged; having plumes. [Obs.]
[1913 Webster]
2. Written with a pen; composed. "Their penned speech."
--Shak.
[1913 Webster]
3. Enclosed in a pen; -- of animals.
[PJC]