"-ize" vs "-ise"

by Mark Israel
 
     [This is a fast-access FAQ excerpt.]
The following verbs are always spelled with "-ise":  advertise,
advise, arise, chastise, circumcise, comprise, compromise, demise,
despise, devise, disguise, enterprise, excise, exercise,
(dis/en)franchise, improvise, incise, merchandise, premise, reprise,
revise, rise, supervise, surmise, surprise, televise.  (At least,
they're *almost* always spelled that way:  "advertize",
"merchandize", and "surprize" ARE listed in some U.S. college
dictionaries, but are not the usual forms anywhere.)   A useful
mnemonic is that, except "improvise", none of these make nouns in
"-isation", "-ization", or "-ism".  (Exceptions in the other
direction are "aggrandize", "capsize", "recognize", and verbs from
which no verb "-ization" has been formed because the parent or
cognate noun already had the desired meaning.)
   "Apprise" means "to inform"; "apprize" means "to appreciate".
U.K. "prise open" = U.S. "pry open".
   "Exorcize" is most commonly spelled "exorcise" in the U.S.,
though "exorcize" (which Fowler would have recommended) also occurs.
   For other verbs, "-ize" is usual in the U.S. and recommended by
Fowler, although "-ise" is also used in the U.K.  Fowler recommends
"-yse" in "analyse", "catalyse", and "paralyse", although "-yze" is
usual in the U.S.