Webster's Revised Unabridged Dictionary · 1913

Becalm

Becalm ({not transcribed}) , transitive verb

1.
To render calm or quiet; to calm; to still; to appease.
Soft whispering airs... becalm the mind. — Philips
2.
To keep from motion, or stop the progress of, by the stilling of the wind; as, the fleet was becalmed.