A social media phenomenon in which older pictures (such as childhood photos) are posted on Thursday with the phrase (often abbreviated "TBT") as an accompanying hashtag or caption. I'm going to post my second grade class picture for throwback Thursday! Me at my senior prom! #throwbackThursday

One week from the day specified. Primarily heard in UK. I'm flying to Ireland a week on Saturday for my brother's wedding. We need that report finished a week tomorrow.

One week before the day specified. They only gave me the assignment a week yesterday, so I'm really stressed out about getting it finished by tomorrow. Chris left on his work trip a week last Tuesday.