What is the meaning of Eighty-eight?

Number between eighty-seven and eighty-nine; decimal 88

An abbreviation for 'Hugs and kisses' in amateur radio. Used especially in Morse code.

A piano (from the number of keys)

A butterfly of the genera Callicore, Perisama, or Diaethria, some of which have a pattern on their wings similar to the digits "88".

Source: wiktionary.org