POSTMARKING is a playable word

postmark Scrabble® Dictionary

verb
postmarked, postmarking, postmarks
to stamp mail with an official mark
1198 Playable Words can be made from "POSTMARKING"
   2-Letter Words (34 found)
   3-Letter Words (162 found)
   9-Letter Words (2 found)
   11-Letter Words (1 found)