Originally "throwback Thursday" but now often used on other days. Can now stand for "throwback to" to indicate an old photo, thought, idea, etc. Often used in social media to reminisce, as usually social media is supposed to show the "here/now/recently."
#tbt the time I only drank milk
#tbt me as a cute 5 yearold #tbt corded phones
(T)hrow(b)ack (T)hursday. A social media post that references the past. Basically the same thing that the Timehop app does for you every day. Usually used in the form of a hashtag.
