the GNU version of the Collaborative International Dictionary of English
n. One who modernizes.
The Century Dictionary and Cyclopedia
n. One who modernizes or renders modern. Also spelled moderniser.
Word Usage
"Cameron, a self-described conservative "modernizer" who has embraced gay rights and "green" policies, agreed to give the post of deputy prime minister to the Liberal Democrats 'leader, Nicholas Clegg, a champion of the poor."