Every other boathouse to make do with an instrument (8)
I believe the answer is:
otoscope
'an instrument' is the definition.
(otoscope is a kind of instrument)
'every other boathouse to make do' is the wordplay.
'every other' indicates alternate letters.
'to make do' becomes 'cope' (I am not sure about this - if you are sure you should believe this answer much more).
The alternate letters of 'boathouse' are 'otos'.
'otos'+'cope'='OTOSCOPE'
'with' acts as a link.
Can you help me to learn more?
(Other definitions for otoscope that I've seen before include "It's used to examine 27 ac" , "medical equipment" , "It's used to examine the ear" , "Device for looking in ears" , "Ear examiner" .)