Delayed crossing delta from the south, missing hotel pool (6)

I believe the answer is:
puddle
'pool' is the definition.
(synonyms)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for puddle that I've seen before include "Small pool of muddy water" , "Small amount of standing rainwater" , "Small amount of standing water" , "Small body of standing water" , "A small pool as of rain" .)
