The Collaborative International Dictionary of English v.0.48:

Stray \Stray\, a. [Cf. OF. estrai['e], p. p. of estraier. See
   Stray, v. i., and cf. Astray, Estray.]
   Having gone astray; strayed; wandering; as, a strayhorse or
   sheep.
   [1913 Webster]

   Stray line (Naut.), that portion of the log line which is
      veered from the reel to allow the chip to get clear of the
      stern eddies before the glass is turned.

   Stray mark (Naut.), the mark indicating the end of the
      stray line.
      [1913 Webster]