A Númenórean unit of measure that was translated as “league”, 5000 rangar in length or about 5277 yards, which is very close to an English league = 3 miles or 5280 yards (UT/279, 285). Its original meaning was “stop, pause” as this is the distance where forced marches usually stopped for a rest, and thus it was likely derived from the root ᴹ√DAR “stay, stop” (Ety/DAR).
Quenya
lár
league
lár
noun. league; †stop, pause
lár (1) noun "league", a linear measure, 5000 rangar (q.v.). A ranga was approximately 38 inches, so a lár was "5277 yards, two feet and four inches [ca. 4826 m], supposing the equivalence to be exact" - close enough to our league of 5280 yards to justify this translation. The basic meaning of lár is "pause"; in marches a brief halt was made for each league. (UT:285)