A hotel apparently’s opening: I’ve seen the light! (3)
I believe the answer is:
aha
'i've seen the light' is the definition.
I can't judge whether this defines the answer.
'a hotel apparently's opening' is the wordplay.
'opening' indicates taking the first letters.
The first letters of 'hotel apparentlys' is 'ha'.
'a'+'ha'='AHA'
Can you help me to learn more?
(Other definitions for aha that I've seen before include "Palindromic exclamation of triumph or surprise" , "Cry of triumph" , "Bingo" , "Exclamation of discovery or triumph" , "Exclamation of triumph or mockery, a palindrome" .)