【Address】 , 【accost】 , 【greet】 , 【salute】 and hail all mean to speak to or less often to write or make a sign to a person in recognition or in order to obtain recognition.
【Address】 usually implies formality and definite purpose; it also frequently suggests length of speech or communication ( 【address】 a petition to Congress) <how does one 【address】 a governor?)
it was Franklin, the thick chief mate, who was addressing him —Conrad
【Accost】 adds to 【address】 the idea of speaking first or without being introduced; it implies absence of formality and often suggests boldness or sometimes evil intent <he accosted a passerby and asked for money
the women . . . were accosted by two men who wanted to walk with them —Anderson
【Greet】 usually implies friendliness, goodwill, or cordiality; it is the precise word when welcoming is to be suggested.
the whole town appeared at the station to 【greet】 them
my lord, the Mayor of London comes to 【greet】 you —Shak.
【Salute】 commonly stresses ceremoniousness or observance of courtesies demanded by custom.
the wife of his brother . . . must be saluted every day; but his paternal and maternal kinswomen need only be greeted on his return from a journey —William Jones
then 1 【salute】 you with this kingly title: long live Richard, England's royal king —Shak.
Specifically 【salute】 applies to formal or prescribed acts of recognition.
the soldier saluted his superior officer
the president was saluted with 21 guns
Hail implies heartiness, joyousness, and often noisiness.
he smiled and nodded and saluted to those who hailed him —MasefieId
It often stresses the idea of calling out especially from a distance
