"Wait . . . what?" (3)
(Other definitions for huh that I've seen before include "sorry?" , "Expression of disgust or surprise" , "Palindromic exclamation of disgust or surprise" .)
(Other definitions for whoa that I've seen before include "horsy expression?" , "Instruction to a horse to stop" , "Command to horse to stop or stand still" , "Command for horse to slow or stop" , "Opposite of "Giddy-up!"" .)