Err (2,6)
'err' is the definition.
(I know that err can be written as stray)
This is all the clue.
(Other definitions for stray that I've seen before include "digress" , "Homeless cat" , "Lost pet" , "Go off course" , "out of place" .)
'err' is the definition.
(thesaurus)
This is the entire clue.