physical evidence of a causal agent (e.g.. insect eggs. borer hole. frass) (contrast with symptom).

Merriam-Webster Online Dictionary
sign (noun)
a) a motion or gesture by which a thought is expressed or a command or wish made known
b) - signal
c) a fundamental linguistic unit that designates an object or relation or has a purely syntactic function - signs include words, morphemes, and punctuation
d) one of a set of gestures used to represent language , also - sign language
a mark having a conventional meaning and used in place of words or to represent a complex notion
one of the 12 divisions of the zodiac
a) (1) a character (as a flat or sharp) used in musical notation
(2) - segno
b) a character (as ÷) indicating a mathematical operation , also one of two characters + and − that form part of the symbol of a number and characterize it as positive or negative
a) a display (as a lettered board or a configuration of neon tubing) used to identify or advertise a place of business or a product
b) a posted command, warning, or direction
c) - signboard
a) something material or external that stands for or something spiritual - signifies
b) something indicating the presence or existence of something else - signs of success a sign of the times
c) - presage portent signs of an early spring
d) an objective evidence of plant or animal disease
traces of a usually wild animal - red fox sign
sign (verb)
transitive verb
a) - cross
b) to place a sign on or mark by - signs sign a trail
c) to represent or indicate by a sign
a) to affix a to ratify or attest by hand or seal - signature sign a bill into law sign a confession
b) to assign or convey formally - signed over his property to his brother
c) to write down (one's name)
d) to affix one's name to - a signed review
to communicate by making a sign or by sign language
intransitive verb
to engage or hire by securing the signature of on a contract of employment - often used with up or on
to write one's name in token of assent, responsibility, or obligation - signed for the packages signed with the team for one season
a) to make a sign or - signal
b) to use sign language
sign (Wikipedia)
This biohazard sign is a completely conventional symbol with no inherent relationship to what it represents.
A natural sign in the environment indicating recent human activity.

A sign is an object, quality, event, or entity whose presence or occurrence indicates the probable presence or occurrence of something else. A natural sign bears a causal relation to its object—for instance, thunder is a sign of storm, or medical symptoms signify a disease. A conventional sign signifies by agreement, as a full stop signifies the end of a sentence; similarly the words and expressions of a language, as well as bodily gestures, can be regarded as signs, expressing particular meanings. The physical objects most commonly referred to as signs (notices, road signs, etc., collectively known as signage) generally inform or instruct using written text, symbols, pictures or a combination of these.

The philosophical study of signs and symbols is called semiotics; this includes the study of semiosis, which is the way in which signs (in the semiotic sense) operate.

« Back to Glossary Index