The Hebrew noun/name bohan means 'thumb' or 'big toe' and appears as a place name — the 'Stone of Bohan son of Reuben' — marking a boundary stone in the tribal allotments of Joshua. The specific landmark was perhaps a stone shaped like a thumb or named after a Reubenite hero.
The boundary markers in Joshua 15 and 18 — including the 'Stone of Bohan' — reflect the precision of God's covenant land grants. God does not give Israel a vague territory but specific, delineated boundaries established by identifiable landmarks. This specificity testifies to the reality of the covenant: God's promises are not abstract but concrete, geographical, and historically verifiable. Every landmark in Joshua's surveys is a monument to the faithfulness of God who kept His word to Abraham.