Fill (something) out or fill out (something) chiefly US : to complete (something, such as a form) by providing necessary information
- fill out [=fill in] a form
- fill out an application
- But there are other less obvious savings which can be taken into account if you are prepared to write a few letters and fill out a form or two.
- … there were still many more official forms to fill out before their new life in Israel could begin.
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