Half of bubbly liquid that's inside jacuzzi? (7)

I believe the answer is:
bathtub
'jacuzzi?' is the definition.
I can't tell whether this defines the answer.
'half of bubbly liquid that's inside' is the wordplay.
'half of' indicates taking half.
'liquid' is an anagram indicator.
'inside' means one lot of letters goes inside another.
'bubbly' halved is 'bub'.
'that' anagrammed gives 'atht'.
'bub' placed around 'atht' is 'BATHTUB'.
Can you help me to learn more?
(Other definitions for bathtub that I've seen before include "Washing vessel" , "Soaking receptacle" , "Need this to be clean" , "Archimedes' reputedly was here before his 'Eureka'" , "place to immerse the body" .)