A replacement rule deterministically rewrites one phrase as another. Where dictionary terms are hints, replacement rules are absolute.
Find them in Settings → Custom Dictionary → Replacement rules.
Creating one
Heard…: the phrase to match (e.g. am lin)
Write…: what to write instead (e.g. Amlin)
Aa: tick for case-sensitive matching
Add
Leave the replacement blank to delete the matched phrase from the output. Useful for a verbal tic you'd rather never see written down.
How they're applied
Whole-word, so a rule for lead won't mangle leader
After cleanup, so the rule always wins
Toggleable: flip the switch on a rule to disable it without deleting it
Rule or dictionary term?
Dictionary term: you want the word heard correctly and spelled consistently. Start here.
Replacement rule: recognition keeps producing a specific wrong string and you want it rewritten every time, no exceptions.