sell out

British  

verb

1. Also (chiefly Brit): sell up.  to dispose of (supplies of something) completely by selling

2. informal (tr) to betray, esp through a secret agreement

3. informal (intr) to abandon one's principles, standards, etc

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noun

1. informal a performance for which all tickets are sold

2. a commercial success

3. informal a betrayal

4. informal a person who betrays their principles, standards, friends, etc

sell out Idioms  

1. Dispose of entirely by selling. For example, The rancher finally sold out to the oil company , or The tickets to the concert were sold out a month ago . [Late 1700s]

2. Betray one's cause or colleagues, as in He sold out to the other side . [ Slang ; late 1800s]

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Example Sentences

Everyone underestimates Ashley’s intelligence and Austin’s willingness to sell out justice to ensure they’ll get ahead.

From Salon • Apr. 23, 2026

Tony arrives two hours before kick-off to buy a programme before they sell out, chats to fans and volunteers then notes down the line-ups and goalscorers for his scrapbook.

From BBC • Apr. 7, 2026

Alvarez & Marsal also noted that more biotechs are deciding to sell out rather than go public.

From Barron's • Apr. 6, 2026

So if tickets sell out for one sport during the first drop, more tickets from the same sport could be added for the next drop.

From Los Angeles Times • Mar. 30, 2026

“He would think it was like quitting. He’d feel it was a cowardice. No, he will never sell out, and if he did I don’t think he would live a week.”

From "East of Eden" by John Steinbeck