Long-distance runner receiving bravos on run is a dainty eater (7)

'a dainty eater' is the definition.
The definition suggests a singular noun which matches the answer.

'long-distance runner receiving bravos on run' is the wordplay.
'long-distance runner' becomes 'nile' (long river - something that runs).
'receiving' is an insertion indicator.
'bravos' becomes 'bb' (two B's - 'bravo' in the phonetic alphabet).
'on' means one lot of letters go next to another.
'run' becomes 'r' (cricket abbreviation).
'nile' placed around 'bb' is 'nibble'.
'nibble'+'r'='NIBBLER'

'is' is the link.

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