unknown

If something is unknown, it's not familiar understood, like the unknown path through the woods you've never explored or your brother's unknown reasons for staying late after school.

When you're aware ofor familiar with something, you can describe it as known. Add the prefix un-, or "not," and you get unknown. You'll often find this adjective in the phrase "unknown territory," as in "I totally understand algebra, but calculus is unknown territory." And as a noun, the unknown sometimes represents a whole category of mysterious things: "Our fear of the unknown keeps us from traveling to new places."

Primary Meanings of unknown

1.
adjn
not known
an unknown and unexplored region
2.
n
a variable whose values are solutions of an equation
Full Definitions of unknown
1

adj not known

“an unknown amount”
“an unknown island”
“an unknown writer”
“an unknown source”
Synonyms:
unacknowledged
not recognized or admitted
unfamiliar
not known or well known
inglorious
not bringing honor and glory
chartless, uncharted, unmapped
(of unknown regions) not yet surveyed or investigated
little-known
unknown to most people
unbeknown, unbeknownst
(usually used with `to') occurring or existing without the knowledge of
undiagnosed
eluding diagnosis
undiscovered, unexplored
not yet discovered
unheard-of
previously unknown
unidentified
not yet identified
Antonyms:
known
apprehended with certainty
acknowledged
recognized or made known or admitted
familiar
well known or easily recognized
glorious
having or deserving or conferring glory
best-known
most familiar or renowned
better-known
more familiar or renowned than the other of two
celebrated, famed, famous, far-famed, illustrious, notable, noted, renowned
widely known and esteemed
identified
having the identity known or established
legendary
so celebrated as to having taken on the nature of a legend
proverbial
widely known and spoken of
well-known
widely or fully known
show more antonyms...

adj not known to exist

“things obscurely felt surged up from unknown depths”
Synonyms:
unsuspected
not suspected or believed likely

adj not known before

“don't let anyone unknown into the house”
Synonyms:
strange
unfamiliar
not known or well known

adj being or having an unknown or unnamed source

“a poem by an unknown author”
Synonyms:
nameless, unidentified, unnamed
anon., anonymous
having no known name or identity or known source

adj not famous or acclaimed

Synonyms:
obscure, unsung
inglorious
not bringing honor and glory

n an unknown and unexplored region

“they came like angels out the unknown
Synonyms:
terra incognita, unknown region
Type of:
region
a large indefinite location on the surface of the Earth

n anyone who does not belong in the environment in which they are found

Synonyms:
alien, stranger
Antonyms:
acquaintance, friend
a person with whom you are acquainted
Types:
foreigner, outsider
someone who is excluded from or is not a member of a group
transalpine
one living on or coming from the other side of the Alps from Italy
Type of:
interloper, intruder, trespasser
someone who intrudes on the privacy or property of another without permission
2

n a variable whose values are solutions of an equation

Synonyms:
unknown quantity
Type of:
variable
a symbol (like x or y) that is used in mathematical or logical expressions to represent a variable quantity

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