Mary Jane is a different name for Marijuana.  Also a song from Rick James which really explains it well.
Lyrics from Mary Jane sung by Rick James...
I'm in love with Mary Jane.
She's my main thing.
She makes me feel alright.
She makes my heart sing.
I'm in love with Mary Jane.
She's my main thing.
She makes me feel alright.
She makes my heart sing.
by R 2 J Through K January 8, 2005
 Get the Mary Janemug.
Get the Mary Janemug. Mary Jane is the hottest girl you will ever meet. She is very sweet and extremely lovable. shes funny and she will have the cutest laugh ever. If you meet a mary jane keep her forever and ever and ever and ever and ever and ever and ever and ever and make her your best friend or your girlfriend!
by mzhvl; January 1, 2012
 Get the Mary Janemug.
Get the Mary Janemug. by ZT May 9, 2005
 Get the mary-janemug.
Get the mary-janemug. Rick James said he was in love with *Mary Jane. I think you could believe that! He wasn't the only one either.
by talk2me-JCH2 September 9, 2023
 Get the *Mary Janemug.
Get the *Mary Janemug. Another word/phrase for marijuana, It is no particular type of marijuana, just a slang word for it in general. Also can be shortened as just Mary, not Mary Jane
by G-Fo March 3, 2005
 Get the Mary Janemug.
Get the Mary Janemug. "Let's smoke that bowl, hit the bong,
And then take that finger off of that hole,
Plug it, unplug it,
Don't straaaain, I love you Mary Jane,
She never complains, when I hit Mary,
With that flame, I light up the cherry,
She's so good to me, when I pack a fresh bowl I clean the
screen,"
-Cypress Hill; Hits from the Bong; Black Sunday
And then take that finger off of that hole,
Plug it, unplug it,
Don't straaaain, I love you Mary Jane,
She never complains, when I hit Mary,
With that flame, I light up the cherry,
She's so good to me, when I pack a fresh bowl I clean the
screen,"
-Cypress Hill; Hits from the Bong; Black Sunday
by azrael March 23, 2005
 Get the mary janemug.
Get the mary janemug. 