Synonyms for Stray (same or very similar meaning)
WordNet sense 1 (homeless cat):
alley cat
WordNet sense 2 (wander from a direct course or at random):
drift, err
WordNet sense 3 (move about aimlessly or without any destination, often in search of food or employment):
cast, ramble, range, roam, roll, rove, swan, tramp, vagabond, wander
WordNet sense 4 (lose clarity or turn aside especially from the main subject of attention or course of argument in writing, thinking, or speaking):
digress, divagate
WordNet sense 5 (not close together in time):
isolated
WordNet sense 6 (recurring in scattered and irregular or unpredictable instances):
sporadic
From the ODE community, based on WordNet
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