known (adj.) Look up known at Dictionary.com
mid-13c., knouen, "well-known, famous, notorious," past participle adjective from know (v.). From early 14c. as "recognized, not secret; familiar, not strange." As a noun, "that which is known," by 1863; earlier "famous person" (1835). In Middle English it meant "one's acquaintances." To make (something) known is from mid-14c.