What is "retain wall"

Retain \Re*tain"\ (r[-e]*t[=a]n"), v. t. [imp. & p. p. Retained (r[-e]*t[=a]nd"); p. pr. & vb. n. Retaining.] [F. retainir, L. retinere; pref. re- re- + tenere to hold, keep. See Tenable, and cf. Rein of a bridle, Retention, Retinue.]

1. To continue to hold; to keep in possession; not to lose, part with, or dismiss; to restrain from departure, escape, or the like. ``Thy shape invisible retain.''
   --Shak.

   Be obedient, and retain Unalterably firm his love entire.
   --Milton.

   An executor may retain a debt due to him from the testator.
   --Blackstone.

2. To keep in pay; to employ by a preliminary fee paid; to hire; to engage; as, to retain a counselor.

   A Benedictine convent has now retained the most learned father of their order to write in its defense.
   --Addison.

3. To restrain; to prevent. [Obs.]
   --Sir W. Temple.

   Retaining wall (Arch. & Engin.), a wall built to keep any movable backing, or a bank of sand or earth, in its place; -- called also retain wall.

   Syn: To keep; hold; restrain. See Keep.