An onion dome is a dome whose shape resembles an onion. Such domes are often larger in diameter than the tholobate upon which they sit, and their height usually exceeds their width. They taper smoothly upwards to a point.

It is a typical feature of churches belonging to the Russian Orthodox church. There are similar buildings in other Eastern European countries, and occasionally in Western Europe: Bavaria (Germany), Austria, and northeastern Italy. Russian architectural design, is the meaning behind its shape. As mentioned above, initially, the onion dome’s purpose was to prevent the snow from piling on the roof. But then, in 1917, a famous religious philosopher, Yevgeny Trubetskoy, stated that the shape of the onion dome resemble candles. Different colors have a different meaning. You will see onion domes in the color of gold appearing in many cathedrals. This is because the gold color symbolizes heavenly glory. There are also churches with blue onion domes on it. This color is to represent the Mother of God. Christians do not only honor the mother of God but also the saints. This appreciation displayed by the green or silver onion domes.