d-v-r — to speak; word, thing
ד.ב.ר (daber) gives Hebrew both "word" and "thing" in a single noun, davar — plus the Ten Commandments, the book of Deuteronomy, and the word for wilderness.
The word family
Every word below is built on ד.ב.ר. Same three letters, different vowels and prefixes.
This root barely exists in Pa'al. The everyday verb for speaking is Pi'el.
Both senses are live at once. Context decides, and sometimes deliberately does not.
The Hebrew name of Deuteronomy, from its opening line: "these are the words".
עֲשֶׂרֶת הַדִּבְּרוֹת (aseret ha-dibrot) — what English calls the Ten Commandments, but the Hebrew says "the Ten Sayings".
Shares the letters, and the connection is debated rather than settled — worth knowing as an open question, not a fact.
What I tell students about this root
The single most useful thing here is that davar is "word" and "thing" at the same time. A Hebrew speaker asking מַה הַדָּבָר? is asking what the matter is, using the noun for word. That overlap does real theological work in Genesis 1, where speech and existence are not two separate events.