Exact historical dictionary sense
Lower in Webster's 1913 dictionary
The 1913 record labels lower as verb. Its source-bounded etymology and selected historical definition appear below.
WEBSTER 1913verb
Lower
[OE. lowren, luren; cf. D. loeren, LG. luren. G. lauern to lurk, to be on the watch, and E. leer, lurk.]
Cross-verified historical senseHeadwordlower
Part of speechverb
Historical etymology[OE. lowren, luren; cf. D. loeren, LG. luren. G. lauern to lurk, to be on the watch, and E. leer, lurk.]
Selected historical definitionTo be dark, gloomy, and threatening, as clouds; to be covered with dark and threatening clouds, as the sky; to show threatening signs of approach, as a tempest.
Signed record IDwebster1913-lower-verb-f19a71b61d59
Source locatorCIDE.L, paragraph 7048; Gutenberg eBook 664
Quick answer
In Webster's Revised Unabridged Dictionary (1913), "lower" is labeled verb. Its etymology is recorded as: "[OE. lowren, luren; cf. D. loeren, LG. luren. G. lauern to lurk, to be on the watch, and E. leer, lurk.]" The selected historical definition says: "To be dark, gloomy, and threatening, as clouds; to be covered with dark and threatening clouds, as the sky; to show threatening signs of approach, as a tempest."