Mike Powell to Denis Mosko:

DM>> What  is  grin  ?  because  I  learn English from echo,
DM>> Friend.
MP> It means a "smile."

Not quite,  on  account  of  grin's  negative  connotations.
Consider,  if you will, Son Houses's great song "Grinnin' in
your face".  I think its best recording is by  Son  himself,
done acapella during the 1965 blues festival:

  Don't you mind people grinnin' in your face
  Don't mind people grinnin' in your face
  You just bear this in mind, a true friend is hard to find
  Don't you mind people grinnin' in your face

Unfortunately  I  don't  seem  to have it at hand in digital
form, but can easily upload it should you be interested.

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