D defs.my
Entry 2 senses Webster, 1913

Decern

/dĭsûrnʹ/ · De·cern · IPA /dɪˈsɝn/
01 v. t. To perceive, discern, or decide.
  1. 1.
    To perceive, discern, or decide.[Obs.]
  2. 2.
    To decree; to adjudge.(Scots Law)