411 REFERENCE · Wiktionary
R2R
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
Appendix:Variations of "rr"
English
Noun
-
Roll-to-roll processing
en printing en roll-to-roll processing.
en printing en reel-to-reel processing.
en reduplicated coordinated pairs
en number homophones