Definition of "Sign" :

noun: structure displaying a board on which advertisements can be posted

"The highway was lined with signboards."

noun: a perceptible indication of something not immediately apparent (as a visible clue that something has happened)

"He showed signs of strain."

noun: any nonverbal action or gesture that encodes a message

"Signals from the boat suddenly stopped."

noun: a public display of a message

"He posted signs in all the shop windows."

noun: a character indicating a relation between quantities

"Don't forget the minus sign."

noun: a gesture that is part of a sign language

noun: a fundamental linguistic unit linking a signifier to that which is signified

"The bond between the signifier and the signified is arbitrary."

noun: an event that is experienced as indicating important things to come

"It was a sign from God."

noun: (astrology) one of 12 equal areas into which the zodiac is divided

noun: having an indicated pole (as the distinction between positive and negative electric charges)

"Charges of opposite sign."

noun: (medicine) any objective evidence of the presence of a disorder or disease

"There were no signs of asphyxiation."

verb: make the sign of the cross over someone in order to call on God for protection; consecrate

verb: be engaged by a written agreement

"He signed to play the casino on Dec. 18."

verb: communicate in sign language

"I don't know how to sign, so I could not communicate with my deaf cousin."

verb: mark with one's signature; write one's name (on)

"She signed the letter and sent it off."

verb: communicate silently and non-verbally by signals or signs

"He signed his disapproval with a dismissive hand gesture."

verb: place signs, as along a road

"Sign an intersection."

verb: engage by written agreement

"They signed two new pitchers for the next season."

verb: approve and express assent, responsibility, or obligation

"Have you signed your contract yet?."

adjective: used of the language of the deaf