Letters that make high-up
g, p, h, i, u are letters that make 'high-up'
1 possible definitions for 'high-up'
Under this definition, high-up is a noun and has the following properties:
very important person, VIP, dignitary, panjandrum, high muckamuck have the same meaning as 'high-up'
'high-up' can be a type of important person, influential person, personage.