verb

• (transitive, obsolete) To make calm or still; make quiet; calm.
  "[…] there is neither house nor landes, nor great store of gold & siluer, nor honor and noblenes of blood, nor greatnes of office, and estate, nor the grace and vehemencie of speach, which doth so much lighten, and so sweetlie becalme the life of man, as an vndefiled conscience […]"
• (transitive, nautical) To deprive (a ship) of wind, so that it cannot move (usually in passive).
  "1555, Richard Eden (translator), The decades of the newe worlde or west India conteynyng the nauigations and conquestes of the Spanyardes by Peter Martyr d’Anghiera, London: Edward Sutton, “The seconde v[o]yage to Guinea,” p. 351, […] there we were becalmed the .xx. day of Nouember from .vi. of the clocke in the mornynge vntyll foure of the clocke at after none."