In a recreational manner, for recreation, for fun or entertainment.(adverb)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "recreationally" in a sentence
"The guy popping Ritalin recreationally is really going to go score an 8-ball if they can't get their pills anymore?"
"The question I have is that if, even after doing this, some small subset of the population still uses heroin recreationally, do we allow those people to purchase it through a pharmacy in order to undercut the black market?"
"People who begin using "recreationally" -- a weekend here, a weekend there -- commonly find themselves, without warning, using on a weekly basis, then on a daily basis."