\Di*mid"i*ate\, a. [L. dimidiatus, p. p. of dimidiare
to halve, fr. dimidius half. See {Demi-}.]
1. Divided into two equal parts; reduced to half in shape or
   form.
2. (Biol.)
   (a) Consisting of only one half of what the normal
       condition requires; having the appearance of lacking
       one half; as, a dimidiate leaf, which has only one
       side developed.
   (b) Having the organs of one side, or half, different in
       function from the corresponding organs on the other
       side; as, dimidiate hermaphroditism.

\Di*mid"i*ate\, v. t. [imp. & p. p. {Dimidiated}; p.
pr. & vb. n. {Dimidiating}.]
1. To divide into two equal parts. [Obs.] --Cockeram.
2. (Her.) To represent the half of; to halve.