The slang term
OG meaning
short for "Original Gangster", a word that was first used in the hip-hop culture and became famous thanks to rapper Ice-T. However, the term has evolved a lot since then and nowadays it's most commonly used to refer someone who is genuine, skilled and/or widely recognized in his/her respective field. In chats and text messaging, referring to someone as an "OG" is generally a positive recognition implying that they are original, influential, or that they have been around long enough to gain the respect and admiration of others.