Evidence of gunfire touching ship's side (6)
I believe the answer is:
report
'evidence of gunfire' is the definition.
'report' can be an answer for 'gunfire' (thesaurus). I am not sure about the 'evidence of' bit.
'touching ship's side' is the wordplay.
I cannot quite understand how this works, but
'touching' could be 're' (both can mean concerning or relating to) and 're' is present in the answer.
'side' could be 'port' (port is a kind of side) and 'port' is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for report that I've seen before include "School student's assessment" , "A crack" , "Narrative given by porter" , "Statement of fact" , "Teacher's assessment" .)