The Collaborative International Dictionary of English v.0.48:

vernal \ver"nal\ (v[~e]r"nal), a. [L. vernalis, fr. vernus
   vernal, ver spring; akin to Gr. 'e`ar, Skr. vasanta, Icel.
   v[=a]r, and E. Easter, east.]
   1. Of or pertaining to the spring; appearing in the spring;
      as, vernal bloom.
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            And purple all the ground with vernal flowers.
                                                  --Milton.
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   2. Fig.: Belonging to youth, the spring of life.
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            When after the long vernal day of life. --Thomson.
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            And seems it hard thy vernal years
            Few vernal joys can show?             --Keble.
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   Vernal equinox (Astron.), the point of time in each year
      when the sun crosses the equator when proceeding
      northward, about March 21, when day and night are of
      approximately equal duration. The beginning of the Spring
      season.

   Vernal grass (Bot.), a low, soft grass (Anthoxanthum
      odoratum), producing in the spring narrow spikelike
      panicles, and noted for the delicious fragrance which it
      gives to new-mown hay; -- also called sweet vernal
      grass. See Illust. in Appendix.

   Vernal signs (Astron.), the signs, Aries, Taurus, and
      Gemini, in which the sun appears between the vernal
      equinox and summer solstice.
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