PREFIXING is a playable word

prefix Scrabble® Dictionary

verb
prefixed, prefixing, prefixes
to add as a prefix (a form affixed to the beginning of a root word)
102 Playable Words can be made from "PREFIXING"
   2-Letter Words (13 found)
   6-Letter Words (9 found)
   8-Letter Words (2 found)
   9-Letter Words (1 found)