In most Slavic languages the word for bread is chleb or something similar: Czech & Polish: chleb, Slovak: chlieb, Russian & Belarusian: хлеб, Ukrainian: хліб, Bulgarian: хляб, Macedonian: леб.
These words all comes from the Proto-Slavic *xlěbъ (bread), from the Proto-Germanic *hlaibaz (bread). [source]. *hlaibaz is also the root of the English word loaf, the German Laib (loaf), and words for loaf in other Germanic languages [source].
However, in Slovenian the word for bread is kruh, which means circle or ring in Czech, although the Czech word probably comes from a different root [source]. It comes from the Proto-Slavic *kruxъ (chunk, bread), which comes from *krews (crush, break) [source].