salutation

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A polite expression of greeting or goodwill.
• noun Greetings indicating respect and affection; regards.
• noun A gesture of greeting, such as a bow or kiss.
• noun A word or phrase of greeting used to begin a letter or message.

from The Century Dictionary.

• noun The act of saluting or greeting, or of paying respect or reverence by customary words or actions or forms of address; also, that which is spoken, written, or done in the act of saluting or greeting.
• noun Quickening; excitement; stimulus.
• noun Synonyms Greeting, Salutation, Salute. A greeting generally expresses a person's sense of pleasure or good wishes upon meeting another. Salutation and salute are by derivation a wishing of health, and are still modified by that idea. A salutation is personal, a salute official or formal; salutation suggests the act of the person saluting, salute is the thing done; a salutation is generally in words, a salute may be by cheers, the dipping of colors, the roll of drums, the firing of cannon, etc.

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

• noun The act of saluting, or paying respect or reverence, by the customary words or actions; the act of greeting, or expressing good will or courtesy; also, that which is uttered or done in saluting or greeting.

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

• noun A greeting, salute, or address; a hello.
• noun The act of greeting.
• noun The title in your name, such as Mr, Mrs, Ms., Dr. or Rev..

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

• noun word of greeting used to begin a letter
• noun (usually plural) an acknowledgment or expression of good will (especially on meeting)
• noun an act of honor or courteous recognition