English definition of “sign”
/saɪn/ noun [C]
PROOF › something which shows that something is happening: Flowers are the first sign of Spring. [+ (that)] It's a sign that things are improving. Staff are showing signs of strain.
NOTICE › a symbol or message in a public place which gives information or instructions: a road sign a 'no-smoking' sign
SYMBOL › a symbol which has a particular meaning: a dollar/pound sign the sign of the cross
MOVEMENT › a movement you make to give someone information or tell them what to do → See also star sign