Yadin is a Hebrew name, used as both a first and last name, which comes from the root word "din" (law or judgment). Yadin is the future tense of the verb conjugated in the third person, meaning “(he) will enact justice,” “(he) will make law” or “(he) will judge.”
Antiquity
The word Yadin appears in the Hebrew Bible (Genesis 49:16, Deuteronomy 32:36, I Samuel 2:10 and elsewhere) usually referring to the almighty who will judge nations "Yadin Amim Bemeisharim" and similarly in other contexts.
Within the context of some references it is also argued that "Yadin" means "will take vengeance" (as in Devarim 32:36 and Tehillim 110:6) and not "will judge." According to this interpretation, the pasuk refers to Shimshon taking vengeance on the Pelishtim on behalf of the people.
Other references to Yadin define it as “God will Judge”