waif

noun

1. 1

   A castaway; a homeless child.

2. 2

   (of a plant outside its native range) A plant that has been introduced but is not persistently naturalized.

3. 3

   Goods found of which the owner is not known; originally, such goods as a pursued thief threw away to prevent being apprehended, which belonged to the king unless the owner made pursuit of the felon, took him, and brought him to justice.

4. 4

   Hence, anything found, or without an owner; that which comes along, as it were, by chance.