Definition of "vigilant"

vigilant

/ˈvɪd͡ʒɪlənt/

adjective
comparative more vigilant, superlative most vigilant
1. Watchful, especially for danger or disorder; alert; wary
2. (heraldry, rare) In vigilance.
  Quotations
  von der LUTKE / Argent, a crane vigilant proper. AG. Carl von der Lutke. Arr. 1857 with the British German Crimea legion. Obtained a grant of land in the Eastern Province of the Cape Colony.
  1972, C. Pama, Heraldry of South African Families: Coats of Arms/ Crests/ Ancestry
  [...] and sharing the same heraldry : argent, a crane, vigilant, or, […]
  1997, Saint Thomas More, More to Cranevelt, Leuven University Press, page 23