1up·stairs 
/ˌʌpˈsteɚz/ adverb
/ˌʌpˈsteɚz/ adverb 1 : on or to a higher floor of a building
▪ When you go upstairs, bring these towels with you. ▪ My in-laws live upstairs. ▪ She was on her way upstairs when she heard a car drive up. 2 informal : in the head : mentally or intellectually
▪ Some say he's a little slow upstairs. [=he's mentally slow; he's not intelligent]
▪ When you go upstairs, bring these towels with you. ▪ My in-laws live upstairs. ▪ She was on her way upstairs when she heard a car drive up.
▪ Some say he's a little slow upstairs. [=he's mentally slow; he's not intelligent]
kick (someone) upstairs — see 1kick
