1. Something that suggests the presence or existence of a fact, condition, or quality.
a. An act or gesture used to convey an idea, a desire, information, or a command: gave the go-ahead sign.
b. Sign language.
a. A displayed structure bearing lettering or symbols, used to identify or advertise a place of business: a motel with a flashing neon sign outside.
b. A posted notice bearing a designation, direction, or command: an EXIT sign above a door; a traffic sign.
4. A conventional figure or device that stands for a word, phrase, or operation; a symbol, as in mathematics or in musical notation.
5. pl.sign An indicator, such as a dropping or footprint, of the trail of an animal: looking for deer sign.
6. A trace or vestige: no sign of life.
7. A portentous incident or event; a presage: took the eclipse as a sign from God.
8. A body manifestation that serves to indicate the presence of malfunction or disease.
9. One of the 12 divisions of the zodiac, each named for a constellation and represented by a symbol.
v.signed, sign·ing, signs
1. To affix ones signature to.
2. To write (ones signature).
3. To approve or ratify (a document) by affixing a signature, seal, or other mark: sign a bill into law.
4. To hire or engage by obtaining a signature on a contract: signed a rookie pitcher for next season; sign up actors for a tour.
5. To relinquish or transfer title to by signature: signed away all her claims to the estate.
6. To provide with a sign or signs: sign a new highway.
7. To communicate with a sign or signs: signed his approval with a nod.
8. To express (a word or thought, for example) by sign language: signed her reply to the question.
9. To consecrate with the sign of the cross.
1. To make a sign or signs; signal.
2. To use sign language.
3. To write ones signature.
To record the arrival of another or oneself by signing a register.
1. To announce the end of a communication; conclude.
2. To stop transmission after identifying the broadcasting station.
3. Informal To express approval formally or conclusively: got the Congress to sign off on the tax proposal.
1. Informal To enlist oneself, especially as an employee: Retired politicians often sign on with top-dollar law firms(New York Times).
2. To start transmission with an identification of the broadcasting station.
To record the departure of another or oneself by signing a register.
To agree to be a participant or recipient by signing ones name; enlist: signed up for military service; signing up for a pottery course.
[Middle English signe, from Old French, from Latin signum; see sekw-1 in Indo-European roots.]
Synonyms: sign, symbol, emblem, badge, mark1, token, symptom, note These nouns denote an outward indication of the existence or presence of something not immediately evident. Sign is the most general: The exile of Gaveston was the sign of the barons triumph (John R. Green). Symbol and emblem often refer to something associated with and standing for, representing, or identifying something else: There was One whose suffering changed an instrument of torture, degradation and shame, into a symbol of glory, honor, and immortal life (Harriet Beecher Stowe). a bed of sweet-scented lillies, the emblem of France (Amy Steedman). Badge usually refers to something that is worn as an insignia of membership, is an emblem of achievement, or is a characteristic sign: a sheriffs badge.Sweet mercy is nobilitys true badge (Shakespeare). Mark can refer to a visible trace or impression (a laundry mark) or to an indication of a distinctive trait or characteristic: Intolerance is the mark of a bigot. Token usually refers to evidence or proof of something intangible: sent flowers as a token of her affection. Symptom suggests outward evidence of a process or condition, especially an adverse condition: bad weather that showed no symptoms of improving anytime soon. Note applies to the sign of a particular quality or feature: the eternal note of sadness (Matthew Arnold). See Also Synonyms at gesture.
1. something that indicates or acts as a token of a fact, condition, etc., that is not immediately or outwardly observable
2. an action or gesture intended to convey information, a command, etc.
a. a board, placard, etc., displayed in public and inscribed with words or designs intended to inform, warn, etc.
b. (as modifier) a sign painter
4. an arbitrary or conventional mark or device that stands for a word, phrase, etc.
5. (Mathematics) Mathslogic
a. any symbol indicating an operation a plus signan implication sign
b. the positivity or negativity of a number, quantity, or expression subtraction from zero changes the sign of an expression
6. an indication or vestige the house showed no signs of being occupied
7. a portentous or significant event
8. (Life Sciences & Allied Applications / Zoology) an indication, such as a scent or spoor, of the presence of an animal
9. (Medicine) Med any objective evidence of the presence of a disease or disorder Compare symptom 
10. (Spirituality, New Age, Astrology & Self-help / Astrology) Astrology See sign of the zodiac
1. (Law) to write (ones name) as a signature to (a document, etc.) in attestation, confirmation, ratification, etc.
2.(intr; often foll by to) to make a sign; signal
3. (General Sporting Terms) to engage or be engaged by written agreement, as a player for a team, etc.
4. (Christianity / Ecclesiastical Terms) (tr) to outline in gestures a sign over, esp the sign of the cross
sign /san/ n.1 a board or poster with information on it: The sign on our store says The Clothes Boutique.||a stop sign2 an action or other nonspoken way of communicating: The wave of her hand was a sign of greeting.||He sends her flowers as a sign of love.3 a symbol: The (X) is a multiplication sign. v.1 [I;T] to write ones name on s.t.: He signed a check.2 [I;T] to use finger motions to communicate with people who cant hear: My hearing-impaired sister signed good-bye to me.3 phrasal v.insep. [T] to sign for s.t.: to show that one has received s.t. by signing ones name: My assistant signed for the package.4 phrasal v.insep. [I;T] to sign off on s.t.: to give ones approval: All committee members signed off on the new budget.5 phrasal v. [I] to sign on: to join a group, (syn.) to enlist: When they asked for help, she signed on.6to sign on the dotted line: to show final agreement in a legal or official action: After I signed on the dotted line, I owned a new house!7 phrasal v.sep. [I;T] to sign s.o. in: to write down ones name to show ones presence at a meeting or other gathering, (syn.) to register: We signed in our visitors.||We signed them in.8 phrasal v.insep.to sign s.o. or s.t. out:a. [I;T] s.o.: to write ones name down to show one is leaving: I signed out the salesman when he left this evening.||I signed him out.b. [T] s.t.: to take s.t. out, to borrow: I signed out books at the university library.||I signed them out.9 phrasal v.sep. [T] to sign s.t. away: to give up ownership or rights to s.t.: The mother signed away her house to her children.||She signed it away.10 phrasal v.sep. [T] to sign s.t. over: to change ownership: The president signed over the company to the employees.||She signed it over.11 phrasal v.sep. [I;T] to sign (s.o.) up: to join, agree to do s.t., (syn.) to enroll: I signed up for swimming lessons.-n.signer. adj.phr.signed, sealed, and delivered: successfully ended, agreed upon