ebb in WordNet English dictionary

1. the outward flow of the tide
   ebb  reflux 
   
2. a gradual decline (in size or strength or power or number)
   ebb  ebbing  wane 
   

1. fall away or decline
   "The patient's strength ebbed away"
   ebb 
   
2. hem in fish with stakes and nets so as to prevent them from going back into the sea with the ebb
   ebb 
   
3. flow back or recede
   "the tides ebbed at noon"
   ebb  ebb away  ebb down  ebb out  ebb off