Falsest

[fawls] /fɔls/

adjective, falser, falsest.
1.
not true or correct; erroneous:
a false statement.
2.
uttering or declaring what is untrue:
a false witness.
3.
not faithful or loyal; treacherous:
a false friend.
4.
tending to deceive or mislead; deceptive:
a false impression.
5.
not genuine; counterfeit.
6.
based on mistaken, erroneous, or inconsistent impressions, ideas, or facts:
false pride.
7.
used as a substitute or supplement, especially temporarily:
false supports for a bridge.
8.
Biology. having a superficial resemblance to something that properly bears the name:
the false acacia.
9.
not properly, accurately, or honestly made, done, or adjusted:
a false balance.
10.
inaccurate in pitch, as a musical note.
adverb
11.
dishonestly; faithlessly; treacherously:
Did he speak false against me?
Idioms
12.
play someone false, to betray someone; be treacherous or faithless.
/fɔːls/
adjective
1.
not in accordance with the truth or facts
2.
irregular or invalid: a false start
3.
untruthful or lying: a false account
4.
not genuine, real, or natural; artificial; fake: false eyelashes
5.
being or intended to be misleading or deceptive: a false rumour
6.
disloyal or treacherous: a false friend
7.
based on mistaken or irrelevant ideas or facts: false pride, a false argument
8.
(prenominal) (esp of plants) superficially resembling the species specified: false hellebore
9.
serving to supplement or replace, often temporarily: a false keel
10.
(music)

adverb
11.
in a false or dishonest manner (esp in the phrase play (someone) false)
adj.

late 12c., from Old French fals, faus (12c., Modern French faux) “false, fake, incorrect, mistaken, treacherous, deceitful,” from Latin falsus “deceived, erroneous, mistaken,” past participle of fallere “deceive, disappoint,” of uncertain origin (see fail).

Adopted into other Germanic languages (cf. German falsch, Dutch valsch, Danish falsk), though English is the only one in which the active sense of “deceitful” (a secondary sense in Latin) has predominated. False alarm recorded from 1570s. Related: Falsely; falseness.