Sentence:  I swear, one day, were are all gonna find out that Howard has been pumping 'laughing gas' into Robin's little plexliglass cage. He'll explain that he thought it was a good idea at first, until the gas line broke and they could not stop the flow of '<nowiki/><WSD>giggle juice</WSD>.' 
Meaning of the word marked with <WSD> tags:  Nitrous oxide, laughing gas; (used especially by automotive enthusiasts).