Sevivon is the Hebrew name for a Dreidel or a spinning top.
there are four letters on the sevivon: Nun, Gimel, Heh, Peh(Shin).
The letters represent initials of the words: G-great, N-miracle, H-happened, S-there (when played out of Israel) or P-here (in Israel).

The mentioned miracle happened in the year 165 BC, in the days of the
Maccabim, after the second Temple was defiled by ancient Greece. There was
a need for pure olive oil to light the Menorah in the Temple. The amount of pure
oil was for one day, but the oil lasted for eight days of light - it was a miracle.

Traditional Sevivon is a game piece played in different ways in various Jewish communities. Some just spin a sevivon, read the letters and are reminded of the
great miracle, others play a game called “put-and-take”, using a dreidel marked
with four Hebrew letters: Nun - no win / no lose, Gimmel - taake all, Heh - take half, Shin or Peh - lose. The game is played for candies, nuts and coins which are
received as a present for Hanukah.

During the eight days of Hanukah Jewish children play with a sevivon.

In the old days a sevivon was made of  tin or lead.

The sevivon and its shape is a source of inspiration for stories, songs, games,  decorations and art objects.

The sevivon became a part of  Hanukah as a Jewish folklore item
relying on interpretations:

The four  letters on the sevivon got  new meanings, G.S.N.H
represented Goshen from Genesis 46, 28 "And he sent Judah...
Goshen".

For some communities the four letters represent the days of the
Messiah (358 in Gimatria, numbers that represent letters).

Some say those letters are an abbreviation for "Great President Was Shimon
(Hahashmonai from the days of the Maccabim, when Hebrew money was coined).

When ancient Greece forbade studying the Torah, Jewish children
used the letters on the sevivon to study.
 

The sevivon and its' motion represent Hanukah:

Like the Maccabim, the sevivon stands and falls then stands again.

Jewish kids were forced to run in circles like the sevivon.

There is a Hassidic saying: Even when we are few and weak, and our enemies
are many and strong, one sevivon spin  - can change everything  as happeened
in the days of  the miracle of Hanukah.

In Israel the letters where changed to G-great, N-miracle, H-happened,  P-here (in Israel).