Younger relative is given a hand system for underwater detection (5)
I believe the answer is:
sonar
'underwater detection' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'younger relative is given a hand system' is the wordplay.
'younger relative' becomes 'son'.
'is given' is a charade indicator (letters next to each other).
'hand' becomes 'R' (abbreviation for right, as in the right-hand side).
'system' is an anagram indicator (another version or system with the same letters).
'a' put after 'r' is 'ra'.
'ra' is an anagram of 'ar'.
'son'+'ar'='SONAR'
'for' is the link.
Can you help me to learn more?
(Other definitions for sonar that I've seen before include "Echo sounder - arson (anag)" , "Undersea sensing system" , "Detection system at sea" , "Underwater detection system" , "Underwater location equipment" .)