-ise

from The Century Dictionary.

• noun A termination of verbs, more usually spelled -ize (which see).
• noun An obsolete form of ice.
• noun A termination of some verbs of French origin, equivalent to and of the same origin as -ish, as in advertise, divertise, franchise, enfranchise, etc. It merges with -ise, equivalent to -ize.
• noun A termination of French origin, as in merchandise: also spelled -ice, as in cowardice, and formerly -ize, as in hazardize, etc.
• noun A vulgar colloquialism in Scotland and the northern part of England for I shall.
• noun A vulgar contraction for I is, as used for I am, by negroes and others in the southern United States.

from the GNU version of the Collaborative International Dictionary of English.

• See -ize.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• suffix Used to form verbs from nouns or adjectives, the verbs having the sense of “to make what is denoted by the noun or adjective”.
• suffix Forming abstract nouns of quality or function.