inundation

from The Century Dictionary.

• noun The act of inundating, or the state of being inundated; an overflow of water or other fluid; a flood; a rising and spreading of water over low grounds; hence, an overspreading of any kind; an overflow or superfluous abundance.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act of inundating, or the state of being inundated; an overflow; a flood; a rising and spreading of water over grounds.
• noun An overspreading of any kind; overflowing or superfluous abundance; a flood; a great influx.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The act of inundating, or the state of being inundated; an overflow; a flood; a rising and spreading of water over grounds.
• noun metaphorical An overspreading of any kind; overflowing or superfluous abundance; a flood; a great influx; as, an inundation of tourists.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an overwhelming number or amount
• noun the rising of a body of water and its overflowing onto normally dry land