Sun sign
The sign the Sun was in when you were born. Your core self — and the one horoscopes use.
Over a year the Sun appears to travel once around the zodiac, spending about a month in each sign. Whichever sign it was in on your birthday is your Sun sign.
It describes what makes you feel most alive and the kind of person you're growing into. If you were born near the change-over (a 'cusp'), your exact birth time settles which side you fall on.