Once, this kanji was written almost like ')(', symbolizing a splitting or dividing. Some scholars feel it was later used for eight since it is a readily divided number, others that its shape was close to the old way of showing eight by bending down the three middle fingers and extending the thumb and little finger.
In compound kanji characters, often found as '( \' or '`/', with a meaning of divide/disperse/away/out.
Who knew ascii was so well suited to kanji?