The Ten Commandments, in their original biblical Hebrew, are — The Ten Devarim, or Ten Dibrot (the singular of which is Diber); The Holy of Holies, where the tablets with the Ten Commandments were held in the Jewish temple, is — Dvir; A plague is — Dever.
All these share a common root in biblical Hebrew — D.B.R (ד.ב.ר).
What does this root mean?
Haim Shore Blog 