Avoska (Russian: авоська) or perhaps-bag is a vernacular for a particular type of shopping bag widespread in the former Soviet Union, a nettedsack (setka, сетка). It was a major cultural phenomenon of the everyday Soviet life. It was manufactured of various kind of strings. With the advent of synthetic materials, some of them were made of stretchable string, so that a very small net could be stretched to a very large sack.
The name “avoska” derives from the Russian adverb авось, an expression of vague expectation of luck, in various contexts translated “perhaps”, “just in case”, etc. The term was introduced in 1930s in the context of shortages of consumer goods in the Soviet Union, when many basic things could have been purchased in a shop only by a strike of luck, and people used to carry an avoska in the pocket all the time. The origin of the term is uncertain, with several different attributions.  In particular, in 1970 a popular Soviet comedian Arkady Raikin explained that around 1935 he introduced a character, a simple man with a netted sack in his hands. He used to demonstrate the sack to the spectators and to say “А это авоська. Авось-ка я что-нибудь в ней принесу” (“And this is a what-iffie. What if I bring something in it…”).