To match dialog but not dialogue in vim: dialog\> ...in other regex systems: dialog\b "dialog" as part of a variable name with underscores: :%s

To match dialog but not dialogue in vim: dialog\> ...in other regex systems: dialog\b "dialog" as part of a variable name with underscores: :%s/dialog_/dialogue_/g "dialog" as part of a variable name with CamelCase: :%s/\([dD]\)ialog\([A-Z][A-z]*\)/\1ialogue\2/g You don't need to capture every case in a single regex substitution, you can use a handful to cover pretty much every case though. This sort of change should not take more than a few minutes max of developer time. I don't have experience with them, but I imagine an IDE with refactoring support should make these sort of changes trivial.