Student or Learner
Do you happen to remember what he was wearing by any chace?
What is the meaning of the red part?
by any chance = accidental adj,, accidentally adv., at random, by accident, fortuitously
used in inquiring about the possibility of something
Example: Are you by any chance free tonight?
accidental = occurring unexpectedly,unintentionally, or by chance.
fortuitously = happening by a fortunate accident or chance,
happening by chance, especially in a way that has a good result
"Have you by any chance seen my book?"