A day, moment, pound, etc. or two
Definition 1 of 1
Pro Tip 1/3General Vagueness
This phrase implies an unspecified, approximate amount or duration, not requiring precision. 
I'll need a day or two to review your work.
Pro Tip 2/3Understated Change
Often used to downplay the amount of time or change, suggesting it's minor or not daunting. 
Let's give it a moment or two to cool down.
Pro Tip 3/3Casual Conversations
Fits well in informal discussions where precise times or numbers aren't crucial. 
I lost a pound or two after my morning runs.