Colonize means to send citizens to a different land to establish a settlement and thereby establish political control for the home country. Colonize may also refer to establishing plants or animals in a new habitat. Colonize may be used as either a transitive verb which is a verb that takes an object, or an intransitive verb, which takes no object. The North American spelling is colonize, related words are colonizes and colonized, the adjective colonizable and the nouns colonizer and colonization.
Colonise is the preferred British spelling. Related words are colonises and colonised, the adjective colonisable and the nouns coloniser and colonisation. The American spellings are also considered correct and are gaining acceptance around the world
Colonize and colonise are examples of a group of words that are spelled with a “z” in American English and with an “s” in British English. Colonize comes from the Latin colonus, which means tiller of the soil, farmer.
Examples
The second man on the moon is teaming up with the Florida Institute of Technology to develop a master plan to colonize the red planet in less than 25 years. (TIME)
Whether your desire is to someday sell the business, become rich and famous, overtake Facebook, or colonize Mars , you must both possess a shared goal. (Forbes)
So the Spanish king gave Mendendez, one of his most experienced admirals, two main tasks: first drive the French out and then colonize and evangelize La Florida. (The Florida Times-Union)
Told from the perspective of the Moroccan slave Estebanico, mentioned in passing in official accounts, it depicts the doomed saga of the Spanish conquistador Pánfilo de Narváez who, in 1527, led an expedition to colonise Florida, which led to horrendous consequences for the unprepared settlers. (The Guardian)
However, what is deeply sad about the move is that it has ignored the painful history of South Africa, the many wars our people, black and white, fought against the English and all those who sought to colonise us. (The Sunday Independent)