Matryoshka

The nesting doll – Matryoshka is the most famous Russian toy, a symbol of Russia, and considered to be one of the phenomenons in the world folk art.

A matryoshka doll is a set of wooden dolls of decreasing size placed one inside the other. The first Russian nested doll set was carved in 1890. Traditionally the outer layer is a woman, dressed in a sarafan, a long and shapeless traditional Russian peasant jumper dress. The figures inside may be of either gender; the smallest, innermost doll is typically a baby lathed from a single piece of wood. 

The name of the toy is a diminutive from Matriona, a popular Russian name at the time. It has also been pointed out that there may be a connection with the Latin mater, which is supported by the idea itself: a large toy that shelters other smaller ones. However, in the beginning they represented men as well. They also represented entire families, statesmen, czars and also dolls celebrating certain events or holidays. Today, the name has become the symbol of motherhood and fertility. 

Matryoshkas are also used metaphorically, as a design paradigm, known as the "matryoshka principle" or "nested doll principle". It denotes a recognizable relationship of "object-within-similar-object" that appears in the design of many other natural and man-made objects. The onion metaphor is of similar character. If the outer layer is peeled off an onion, a similar onion exists within.