a lot: a small marked object thrown or drawn to settle a question, so that the outcome is nobody's choice
A lot was a small object: a pebble, a piece of broken pottery, a marked stick. It was dropped into a jar and shaken out, or simply thrown on the ground, and wherever it landed gave the answer. Because nobody could steer the result, lots settled the kinds of questions that would otherwise start a fight, such as who takes which piece of land, whose turn of duty comes next, or which of several men gets a job.
The Greek word names the token itself and not the practice, so it almost always travels next to a verb of throwing or handing out. All four Gospels use it of the soldiers dividing the clothes of the crucified Jesus, echoing the wording of Psalm 22:18, and that scene is the one most readers already picture. In Acts 1:26 the eleven use lots to fill the place Judas left, and the account says the lot "fell on" Matthias.
The same object carries very different assumptions depending on who is holding it. Roman soldiers throwing for a garment are dividing loot and expect nothing but a random result. Israel's Scriptures treat the falling of the lot as a decision God himself makes, which is why the Hebrew word behind it (גּוֹרָל) is used for the way the promised land was divided, and why the disciples pray before they cast. Nothing in the object itself tells you which of those two things is going on.