Is it possible to have marijuana induced gynecomastia?

Yes: Marijuana is one of the known causes of gynecomastia. True gynecomastia needs to be distinguished from fat (obesity). Stopping the weed will probably help, but it will take a while.

Yes: Gynecomastia comes from the greek meaning "gyne" meaning woman and  "mastos"  meaning breasts.  it refers to abnormal development of large mammary glands in males. Although there may be many “causes”, including the use of marijuana, most cases are idiopathic (no specific cause).