Meaning: close or shut as with a zipper, usually a directive for the mouth or voice
Rewrite 1: staple it!
Rewrite 2: sew it!
Rewrite 3: clamp it!
Rewrite 4: crimp it!
Rewrite 5: glue it!
Rewrite 6: press it!
Comment: There are many ways to secure something that you can use as exchanges for this less common idiom. Keep in mind that there are other uses for the phrase, too. In the technological age, it may be a reference to the ZIP drive and in the non-technological sense it may be a reference to speeding something along, as by speeding the mail using the ZIP code.
More help with writing expressively
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