Chapter Loveable to Lower-case of L by Webster's Dictionary (1913 Edition)

2. To frown; to look sullen.

But sullen discontent sat lowering on her face.

Dryden.

Lower
(Low"er), n. [Obs.]

1. Cloudiness; gloominess.

2. A frowning; sullenness.

Lower-case
(Low"er-case`) a. (Print.) Pertaining to, or kept in, the lower case; — used to denote the small letters, in distinction from capitals and small capitals. See the Note under 1st Case, n., 3.