Wordnet 3.0
NOUN (1)
1.
a believer in colonialism;
The Collaborative International Dictionary of English v.0.48:
colonialist \colonialist\ n.
a believer in or advocate of colonialism[3].
[WordNet 1.5]
WordNet (r) 3.0 (2006):
colonialist
n 1: a believer in colonialism