1. [n]  someone who takes the place of another person
2. [adj]  (botany) of leaves and branches etc; first on one side and then on the other in two ranks along an axis; not paired; "stems with alternate leaves"
3. [adj]  allowing a choice; "an alternative plan"
4. [v]  reverse, as of direction, attitude, or course of action
5. [v]  do something in turns; "We take turns on the night shift"
6. [v]  go back and forth; swing back and forth between two states or conditions
7. [v]  be an understudy or alternate for a role
8. [v]  exchange people temporarily to fulfill certain jobs and functions

ALTERNATE is a 9 letter word that starts with A.

1. \Al*ter"nate\ (?; 277), a. [L. alternatus, p. p. of
   alternate, fr. alternus. See {Altern}, {Alter}.]
   1. Being or succeeding by turns; one following the other in
      succession of time or place; by turns first one and then
      the other; hence, reciprocal.
            And bid alternate passions fall and rise. --Pope.
   2. Designating the members in a series, which regularly
      intervene between the members of another series, as the
      odd or even numbers of the numerals; every other; every
      second; as, the alternate members 1, 3, 5, 7, etc.; read
      every alternate line.
   3. (Bot.) Distributed, as leaves, singly at different heights
      of the stem, and at equal intervals as respects angular
      divergence. --Gray.
   {Alternate alligation}. See {Alligation}.
   {Alternate angles} (Geom.), the internal and angles made by
      two lines with a third, on opposite sides of it. It the
      parallels AB, CD, are cut by the line EF, the angles AGH,
      GHD, as also the angles BGH and GHC, are called alternate
      angles.
   {Alternate generation}. (Biol.) See under {Generation}.
   

2. \Al*ter"nate\ (?; 277), n.
   1. That which alternates with something else; vicissitude.
      [R.]
            Grateful alternates of substantial.   --Prior.
   2. A substitute; one designated to take the place of another,
      if necessary, in performing some duty.
   3. (Math.) A proportion derived from another proportion by
      interchanging the means.
   

3. \Al"ter*nate\ (?; 277), v. t. [imp. & p. p.
   {Alternated}; p. pr. & vb. n. {Alternating}.] [L. alternatus,
   p. p. of alternare. See {Altern}.]
   To perform by turns, or in succession; to cause to succeed by
   turns; to interchange regularly.
         The most high God, in all things appertaining unto this
         life, for sundry wise ends alternates the disposition
         of good and evil.                        --Grew.
   

4. \Al"ter*nate\, v. i.
   1. To happen, succeed, or act by turns; to follow
      reciprocally in place or time; -- followed by with; as,
      the flood and ebb tides alternate with each other.
            Rage, shame, and grief alternate in his breast. --J.
                                                  Philips.
            Different species alternating with each other.
                                                  --Kirwan.
   2. To vary by turns; as, the land alternates between rocky
      hills and sandy plains.
   

1. Describes leaves that grow singly along a stem.
2. Of leaves or other lateral plant organs, borne singly at different heights on the axis; of floral parts, on a different radius, e.g. describing the position of stamens with respect to petals. Compare opposite.