A player is someone who participates in games, sports, theater, music, video games, gambling, historical mechanisms, electronics, or computing, involving activities such as playing games, acting, playing musical instruments, gaming, gambling, operating player pianos, using electronic devices, or using software applications for playing audio and/or video media.
One who is playful; one without serious aims; an idler; a trifler.
A participant; one involved in something.
(informal) A person who plays the field rather than having a long-term sexual relationship.