Screeching of small missile (8)
I believe the answer is:
strident
'screeching' is the definition.
(strident can describe a screeching voice)
'small missile' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'missile' becomes 'Trident' (UK nuclear weapons system).
's'+'trident'='STRIDENT'
'of' is the link.
(Other definitions for strident that I've seen before include "(Of a voice) loud and grating" , "making a lot of noise" , "With a loud, harsh voice" , "Loud and harsh over tridents" , "Offensively loud and harsh" .)