Removing duplicate strings/words(not lines) using RegEx(notepad++)

Question

I would like to know a way to remove duplicate words or strings in a text file(not lines) using notepad++ regex find tool.

I only saw ways to remove duplicate lines

Answer 1

I'm not familiar with Notepad++, but assuming it uses standard syntax, replace

\b(\w+)\b([\w\W]*)\b\1\b

with

$1$2