Source : Webster's Revised Unabridged Dictionary (1913)

Annular \An"nu*lar\, a. [L. annularis, fr. annulis ring: cf. F.
   annulaire.]
   1. Pertaining to, or having the form of, a ring; forming a
      ring; ringed; ring-shaped; as, annular fibers.

   2. Banded or marked with circles.

   {Annular eclipse} (Astron.), an eclipse of the sun in which
      the moon at the middle of the eclipse conceals the central
      part of the sun's disk, leaving a complete ring of light
      around the border.

Source : WordNet®

annular
     adj : shaped like a ring [syn: {annulate}, {annulated}, {circinate},
            {circular}, {ringed}, {ring-shaped}, {doughnut-shaped}]