Cher official oneise pjs, Christmas 2016, label says 2XL, but runs smaller. When these were released, the word among Cher fans online was "the onesies run small...order two sizes larger." I did, but this is still too small for me. It's like a middling L. Here are measurements:
Chest: 22.5" one side, 45" all around
Pit to pit: 23"
Sleeve length: 26" long, 9.5" wide
Top to bottom (shoulder to end of leg, not including hood): 55"