1) Body swapping in fiction 2) Dental anesthetic 3) Inhaled anesthetic 4) Slang for nitrous oxide 
[solo] `Laughing Gas` was a song performed by Quiet Riot at all the live performances while Randy Rhoads played with the band. It was never recorded onto an album until a live bootleg performance was enhanced (with rerecorded vocals) and placed on The Randy Rhoads Years. The improvised solo was just over 6 minutes long and contained clips f...
(see Nitrous Oxide) Nitrous Oxide N2O also called laughing gas is a colourless gas with pleasant sweetish odour and taste which when inhaled produces insensibility to pain preceded by mild hysteria or laughter.
See nitrous oxide; odorless inhalation agent that produces relative analgesic (sedation). Used to reduce anxiety and creates a state of relaxation.
A historical term for nitrous oxide. ... Origin: so called because its inhalation sometimes excites a hilarious delirium preceding insensibility ... (05 Mar 2000) ... 
Type: Term Definitions: 1. a historical term for nitrous oxide.
Laughing gas: Nitrous oxide, a gas that can cause general anesthesia. Nitrous oxide is sometimes given in the company of other anesthetic agents but it is never used today as the only anesthetic agent because the concentration of nitrous oxide needed to produce anesthesia is close to the concentration that seriously lowers the blood oxygen level an...
A colorless, sweet-tasting gas that exhibits a pleasing smell when inhaled. The gas is often used as an anesthetic to help individuals remain calm and reduce pain during medical procedures or childbirth. Synonym(s): Nitrous Oxide
Laughing Gas is slang for nitrous oxide.
Dinitrogen oxide
Popular name for nitrous oxide, an anaesthetic