As a Noun: 1. X-RAYS are a type of radiation that can pass through most solid materials. X-RAYS are used by doctors to take a picture and examine the bones or organs inside your body. Note: 1. There appears to be no commonly used Auslan sign for X-RAY. If you know a sign for X-RAY used by you or other Auslan users (deaf people or interpreters) please go to "report missing sign" and supply details. Thank you.