Sign
Part of speech: verb
Definition: To write one's signature on (a document), thus showing authorship. To give legal consent by writing one's signature. To persuade to sign a contract. To write one's signature somewhere. To give autographs. To communicate using sign language.
Part of speech: noun
Definition: A visible indication. A clearly visible object, generally flat, bearing a short message in words or pictures. A traffic sign. A meaningful gesture. Any of several specialized non-alphabetic symbols. An astrological sign. Positive or negative polarity. A linguistic unit in sign language equivalent to word in spoken languages. sign language in general An omen. A property of the body that indicates a disease and, unlike a symptom, is unlikely to be noticed by the patient.
Signal
Part of speech: noun
Definition: An indication given to another person.An on-off light, semaphore, or other device used to give an indication to another person.(of a radio, TV, telephone, internet, etc) An electrical or electromagnetic action, normally a voltage that is a function of time that conveys the information of the radio or TV program or of communication with another party.Useful information.
Part of speech: verb
Definition: To indicate.