Keywords: diagonal, spare, slash, stroke (slash)

Found 2 variants for this sign (click on video to enlarge):

Sign Definition

As a Noun

1. A line that goes in a slanting direction. English = diagonal.
2. A diagonal line that separates letters, words, or numbers, especially a flat or apartment number from the building number. English = slash, stroke.
3. A slanting straight line that joins two opposite corners of a straight-sided shape such as a square or cube. English = diagonal.
4. A score in ten pin bowling in which all the pins are knocked down in two consecutive bowls. English = spare.

As a Verb or Adjective

1. To go in a slanting direction, as if joining two opposite corners of a straight-sided shape such as a square or cube. English = (be) diagonal.