any disease of the mind; the psychological state of someone who has emotional or behavioral problems serious enough to require psychiatric intervention
an acute viral disease of the nervous system of warm-blooded animals (usually transmitted by the bite of a rabid animal); rabies is fatal if the virus reaches the brain
a perceptible indication of something not immediately apparent (as a visible clue that something has happened); "he showed signs of strain"; "they welcomed the signs of spring"
a public display of a (usually written) message; "he posted signs in all the shop windows"
a character indicating a relation between quantities; "don't forget the minus sign"
a gesture that is part of a sign language
a fundamental linguistic unit linking a signifier to that which is signified; "The bond between the signifier and the signified is arbitrary"--de Saussure
(medicine) any objective evidence of the presence of a disorder or disease; "there were no signs of asphyxiation"
be engaged by a written agreement; "He signed to play the casino on Dec. 18"; "The soprano signed to sing the new opera"
communicate in sign language; "I don't know how to sign, so I could not communicate with my deaf cousin"
mark with one's signature; write one's name (on); "She signed the letter and sent it off"; "Please sign here"
communicate silently and non-verbally by signals or signs; "He signed his disapproval with a dismissive hand gesture"; "The diner signaled the waiters to bring the menu"
place signs, as along a road; "sign an intersection"; "This road has been signed"
engage by written agreement; "They signed two new pitchers for the next season"
approve and express assent, responsibility, or obligation; "All parties ratified the peace treaty"; "Have you signed your contract yet?"
acute contagious infection caused by the bacterium Corynebacterium diphtheriae; marked by the formation of a false membrane in the throat and other air passages causing difficulty in breathing
an infective disease caused by sporozoan parasites that are transmitted through the bite of an infected Anopheles mosquito; marked by paroxysms of chills and fever