Okla. Admin. Code § 535:20-9-2
The following words or terms, when used in this Subchapter, shall have the following meaning, unless the context clearly indicates otherwise:
"Drug order" means a prescription drug order issued by a licensed prescriber for medical gas.
"Medical gas" means those gases and liquid oxygen upon which the manufacturer or distributor has, in compliance with federal law and regulations, placed one of several cautions, such as: "RX Only" that replaces "Caution - Federal Law prohibits dispensing without prescription".
"Medical gas distributor" means a person licensed to distribute medical gases on drug orders and to suppliers or other entities licensed to use, administer, or distribute medical gases.
"Medical gas supplier" means a person licensed to supply medical gases only on drug orders.
Okla. Admin. Code § 535:20-9-2