Source : Webster's Revised Unabridged Dictionary (1913)

Custrel \Cus"trel\ (k[u^]s"trel), n. [OF. coustillier. See
   {Coistril}.]
   An armor-bearer to a knight. [Obs.]

Custrel \Cus"trel\, n.
   See {Costrel}. [Obs.] --Ainsworth.