ebb

v. recede, flow back (of the tide); decay, decline, wane

n. flowing back of the tide; recession, decline, changing from better to worse

According to John Scott Redd, Director, National Counterterrorism Center, the Terrorist Identities Datamart Environment, or TIDE, is the U.S. Government's central database on known or suspected international terrorists, and contains all source highly classified information provided by members of the Intelligence Community such as CIA, DIA, FBI, NSA, as well as many others. There are more than 300,000 records in TIDE, which represents over 200,000 unique identities when aliases and transliteration issues are taken into account. From the classified TIDE database, an unclassified extract is provided to the FBI's Terrorist Screening Center, which in turn is used to compile various watch lists such as the TSA's No-fly list, State Department's Consular Lookout and Support System, Homeland Security's Interagency Border Inspection System, and FBI's NCIC (National Crime Information Center) for state and local law enforcement. Redd represented this as a major step forward from the pre-September 11, 2001 status of multiple, disconnected, and incomplete watchlists throughout the government.
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Tides are the cyclic rising and falling of Earth's ocean surface caused by the tidal forces of the Moon and the Sun acting on the oceans. More generally, tidal phenomena can occur in any object that is subjected to a gravitational field that varies in time and space, such as the Earth's land masses or the Moon. (see Other tides).
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v. ebb, flow back, recede

(v. t.)
To cause to flow back.
  

(v. i.)
To return or fall back from a better to a worse state; to decline; to decay; to recede.
  

(v. i.)
To flow back; to return, as the water of a tide toward the ocean; -- opposed to flow.
  

(n.)
The state or time of passing away; a falling from a better to a worse state; low state or condition; decline; decay.
  

(n.)
The reflux or flowing back of the tide; the return of the tidal wave toward the sea; -- opposed to flood; as, the boats will go out on the ebb.
  

(n.)
The European bunting.
  

(a.)
Receding; going out; falling; shallow; low.
  

Noun
1. a gradual decline (in size or strength or power or number)
(synonym) ebbing, wane
(hypernym) decline, diminution
2. the outward flow of the tide
(synonym) reflux
(hypernym) flow, flowing
(part-holonym) ebbtide
(derivation) ebb away, ebb down, ebb out, ebb off
Verb
1. flow back or recede; "the tides ebbed at noon"
(synonym) ebb away, ebb down, ebb out, ebb off
(antonym) tide, surge
(hypernym) recede, fall back, retire
(derivation) reflux
2. hem in fish with stakes and nets so as to prevent them from going back into the sea with the ebb
(hypernym) besiege, beleaguer, surround, hem in, circumvent
3. fall away or decline; "The patient's strength ebbed away"
(hypernym) recede
(derivation) ebbing, wane