Like “Hook”, say, pronounce the H (8)
I believe the answer is:
aspirate
'pronounce the h' is the definition.
(to aspirate a vowel is to pronounce it with an H)
'like hook' is the wordplay.
'like' becomes 'as'.
'hook' becomes 'pirate' (Captain Hook from Peter Pan is a pirate).
'as'+'pirate'='ASPIRATE'
'say' acts as a link.
(Other definitions for aspirate that I've seen before include "Pronounce with full breath" , "challenge to Eliza" , "Introduction of hamadryad, perhaps" , "A Parisian doesn't" , "Breathed consonant" .)