Antonyms of adj well-known

2 senses of well-known

Sense 1
well-known -- (widely or fully known; "a well-known politician"; "well-known facts"; "a politician who is well known"; "these facts are well known")

INDIRECT (VIA known) -> unknown -- (not known; "an unknown amount"; "an unknown island"; "an unknown writer"; "an unknown source")

Sense 2
long-familiar, well-known (prenominal) -- (frequently experienced; known closely or intimately; "a long-familiar face"; "a well-known voice reached her ears")

INDIRECT (VIA familiar) -> unfamiliar -- (not known or well known; "a name unfamiliar to most"; "be alert at night especially in unfamiliar surroundings")

Similarity of adj well-known

2 senses of well-known

Sense 1
well-known -- (widely or fully known; "a well-known politician"; "well-known facts"; "a politician who is well known"; "these facts are well known")
       => known (vs. unknown) -- (apprehended with certainty; "a known quantity"; "the limits of the known world"; "a musician known throughout the world"; "a known criminal")

Sense 2
long-familiar, well-known (prenominal) -- (frequently experienced; known closely or intimately; "a long-familiar face"; "a well-known voice reached her ears")
       => familiar (vs. unfamiliar) -- (well known or easily recognized; "a familiar figure"; "familiar songs"; "familiar guests")