Cheer’s original, 13th-century meaning could equally suggest gloom, for it was the face itself. Via Old French chiere, it is from late Latin cara, face, itself most likely from the Greek for head. It soon had the sense of expression, and one could change cheer (surviving in “be of good cheer”, which was not, then, a tautology).

The Times has a feature called A Quick Word, from which this excerpt has been plucked.