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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