==some people say in line others say on line
both mean waiting to be served like at a box office selling tickets ==
Not according to Merriam-Webster.
in-line:
having the parts or units arranged in a straight line; also : being so arranged
https://www.merriam-webster.com/dictionary/in-line
online:
connected to, served by, or available through a system and especially a computer or telecommunications system (such as the Internet)
https://www.merriam-webster.com/dictionary/online
There's the phrase "fall in line," but that's a bit different as well:
to start to do what one is told or required to do
https://www.merriam-webster.com/dictionary/inline
So the words are not really related in usage.
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