kruhu

Kruhu is the genitive singular form of kruh, a Czech and Slovak noun meaning circle or disk. The base word kruh refers to a two‑dimensional geometric figure in which all points are at the same distance from a center, and it is also used in broader senses such as a social circle or group.

In grammar and usage, kruhu appears in constructions where kruh is in the genitive case. This occurs after numerals, with adjectives, and in expressions indicating possession or relation. Examples include obsah kruhu (area of the circle), obvod kruhu (circumference of the circle), and poloměr kruhu (radius of the circle). The form is also used in phrases like ve vnitřním kruhu (in the inner circle) or kruhu přátel (circle of friends).

Kruhu is common in Czech and Slovak, where it functions as a grammatical form rather than a separate lexical entry. The root kruh has cognates in other Slavic languages, such as Russian krug and Ukrainian krug, with corresponding genitive forms that differ in ending but retain the same general meaning of circle or ring.

Overall, kruhu serves as the genitive singular marker for the noun kruh, enabling expressions that denote a circle’s properties, relations, or membership within a circle. It appears across mathematics, science, education, and everyday language in these languages.