What does the cryptic crossword clue "Wading bird in flock, no tail (4)" mean?

The definition is "Wading bird". The wordplay uses a hidden word. Hidden in "wading bird in flocK, NO Tail" The answer is Knot.

Wading bird in flock, no tail (4)

Telegraph Prize Cryptic #3064 | 25 Down | 2020-07-12 flower