Spelling

Enforces consistent spellings.

Source

extends: consistency
message: "Inconsistent spelling of '%s'"
level: error
ignorecase: true
# We only want one of these to appear.
either:
  advisor: adviser
  centre: center

Example

There is no difference in meaning between center and centre. Center is the preferred spelling in American English, and centre is preferred in varieties of English from outside the U.S.