Source : Webster's Revised Unabridged Dictionary (1913)

June \June\, n. [L. Junius: cf. F. Juin. So called either from
   Junius, the name of a Roman gens, or from Juno, the goddess.]
   The sixth month of the year, containing thirty days.

         And what is so rare as a day in June? Then, if ever,
         come perfect days.                       -- Lowell.

   {June beetle}, {June bug} (Zo["o]l.), any one of several
      species of large brown beetles of the genus {Lachnosterna}
      and related genera; -- so called because they begin to
      fly, in the northern United States, about the first of
      June. The larv[ae] of the June beetles live under ground,
      and feed upon the roots of grasses and other plants.
      Called also {May bug} or {May beetle}.

   {June grass} (Bot.), a New England name for Kentucky blue
      grass. See {Blue glass}, and Illustration in Appendix.

May \May\, n. [F. Mai, L. Maius; so named in honor of the
   goddess Maia (Gr. ?), daughter of Atlas and mother of Mercury
   by Jupiter.]
   1. The fifth month of the year, containing thirty-one days.
      --Chaucer.

   2. The early part or springtime of life.

            His May of youth, and bloom of lustihood. --Shak.

   3. (Bot.) The flowers of the hawthorn; -- so called from
      their time of blossoming; also, the hawthorn.

            The palm and may make country houses gay. --Nash.

            Plumes that micked the may.           --Tennyson.

   4. The merrymaking of May Day. --Tennyson.

   {Italian may} (Bot.), a shrubby species of {Spir[ae]a} ({S.
      hypericifolia}) with many clusters of small white flowers
      along the slender branches.

   {May apple} (Bot.), the fruit of an American plant
      ({Podophyllum peltatum}). Also, the plant itself
      (popularly called {mandrake}), which has two lobed leaves,
      and bears a single egg-shaped fruit at the forking. The
      root and leaves, used in medicine, are powerfully drastic.
      

   {May beetle}, {May bug} (Zo["o]l.), any one of numerous
      species of large lamellicorn beetles that appear in the
      winged state in May. They belong to {Melolontha}, and
      allied genera. Called also {June beetle}.

   {May Day}, the first day of May; -- celebrated in the rustic
      parts of England by the crowning of a May queen with a
      garland, and by dancing about a May pole.

   {May dew}, the morning dew of the first day of May, to which
      magical properties were attributed.

   {May flower} (Bot.), a plant that flowers in May; also, its
      blossom. See {Mayflower}, in the vocabulary.

   {May fly} (Zo["o]l.), any species of {Ephemera}, and allied
      genera; -- so called because the mature flies of many
      species appear in May. See {Ephemeral fly}, under
      {Ephemeral}.

   {May game}, any May-day sport.

   {May lady}, the queen or lady of May, in old May games.

   {May lily} (Bot.), the lily of the valley ({Convallaria
      majalis}).

   {May pole}. See {Maypole} in the Vocabulary.

   {May queen}, a girl or young woman crowned queen in the
      sports of May Day.

   {May thorn}, the hawthorn.

Cockchafer \Cock"chaf`er\, n. [See {Chafer} the beetle.]
   (Zo["o]l.)
   A beetle of the genus {Melolontha} (esp. {M. vulgaris}) and
   allied genera; -- called also {May bug}, {chafer}, or
   {dorbeetle}.

Source : WordNet®

May bug
     n 1: any of various large European beetles destructive to
          vegetation as both larvae and adult [syn: {cockchafer},
          {May beetle}, {Melolontha melolontha}]
     2: any of various large usually brown North American
        leaf-eating beetles common in late spring; the larvae feed
        on roots of grasses etc. [syn: {June beetle}, {June bug},
        {May beetle}]