estray

noun

1. An animal that has escaped from its owner; a wandering animal whose owner is unknown. An animal cannot be an estray when on the range where it was raised, and permitted by its owner to run. A lost animal whose owner is known to the party at hand is not an estray.
2. (archaic)Stray.

   “[...] All the day / Had been a dreary one at best, and dim / Was settling to its close, yet shot one grim / Red leer to see the plain catch its estray.”

verb

1. (archaic)To stray.

   “With other Maids to fiſh upon the Shoar; Estrays apart, and leaves her Company”