Chesil: a town in the far south of Judah, named once in the roll of Judah's towns and called Bethul in the parallel list
The name turns up once, in the long roll of towns that Joshua's account assigns to the tribe of Judah. Judah's share reached down into the dry country in the far south, and the writer simply reels the settlements off one after another: Eltolad, Chesil, Hormah. Nothing at all is said about the place. No story happens there, nobody is described as coming from there, and the name is never used again.
What makes Chesil interesting is what the other lists call it. A few chapters later Joshua goes back over these same southern towns, this time as the share carved out for the tribe of Simeon inside Judah's territory, and the run of names is identical except for this one: Eltolad, Bethul (בְּתוּל), Hormah. The Chronicler covers the same ground again and writes Bethuel (בְּתוּאֵל). The old Greek translation of Joshua puts a fourth form in the slot, Bethel. One town seems to stand behind all of them, and Chesil is the form that matches none of the others.
The spelling is also why the name gets a dictionary entry of its own. Written out in Hebrew it is exactly the everyday word for a thick-headed fool (כְּסִיל), and exactly the word used for the constellation we call Orion (כְּסִיל). Whether the town's name has anything to do with either is unknown. The reference works list the place on its own and make no attempt to derive it, and nothing in the verse hints at a joke or at a meaning behind the name.
Where the town stood is not known. The names around it in the list belong to the arid south, so the general stretch of country is clear enough, but no ruin has been matched to it with any confidence.