have (got) to (do something)

have (got) to (do something)

1. Used to indicate a necessity, requirement, or obligation to do something. You have to start trusting me, or else this relationship will never work. One of us has got to wash the dishes this weekend.
2. Used to indicate something that one believes must be true. If the fuel line is OK, then it's got to be the spark plug that's faulty. Tommy has to be innocent—he just has to!
See also: have
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

have to

Also, have got to. Be obliged to, must. For example, We have to go now, or He has got to finish the paper today. The use of have as an auxiliary verb to indicate obligation goes back to the 16th century; the variant using got dates from the mid-1800s.
See also: have
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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