Answer:
if you are referring to the lamp stand found in the "tent of meeting" within the Hebrew's tabernacle, the seven candles do not symbolize anything other than god's will that it be made that way. if you are referring to the eight candeled lampstand lit during channukah, it is called a chanukiah and symbolizes the 8 days that a one day supply of olive oil for the menorah lasted after the maccabees reclaimed the destroyed Solomon's temple (beit hamikdash) from the Romans after a successful revolt.