n. 1. One who ranges; a rover; sometimes, one who ranges for plunder; a roving robber. [ 1913 Webster ]
2. That which separates or arranges; specifically, a sieve. [ Obs. ] “The tamis ranger.” Holland. [ 1913 Webster ]
3. A dog that beats the ground in search of game. [ 1913 Webster ]
4. One of a body of mounted troops, formerly armed with short muskets, who range over the country, and often fight on foot. [ 1913 Webster ]
5. The keeper of a public park or forest; formerly, a sworn officer of a forest, appointed by the king's letters patent, whose business was to walk through the forest, recover beasts that had strayed beyond its limits, watch the deer, present trespasses to the next court held for the forest, etc. [ Eng. ] Rangers in U.S. national parks and national monuments perform a similar function. [ 1913 Webster +PJC ]