sign

1. A visible fact that shows that something exists or may happen. (countable, uncountable) · Their angry expressions were a clear sign they didn't want to talk.· Those clouds show signs of raining soon.
2. An omen. (countable, uncountable)
3. A property of the body that indicates a disease and, unlike a symptom, can be detected objectively by someone other than the patient. (countable, uncountable) · Signs of disease are objective, whereas symptoms are subjective.
4. A mark or another symbol used to represent something. (countable, uncountable) · The sharp sign indicates that the pitch of the note is raised a half step.· I gave them a thumbs-up sign.
5. A clearly visible object, generally flat, bearing a short message in words or pictures. (countable, uncountable) · The sign in the window advertised a room for rent.· I missed the sign at the corner so I took the wrong turn.
6. A wonder; miracle; prodigy. (countable, uncountable)
7. An astrological sign. (countable, uncountable) · Your sign is Taurus? That's no surprise.
8. Positive or negative polarity, as denoted by the + or - sign. (countable, uncountable) · I got the magnitude right, but the sign was wrong.

Plural signs