adj. 1
Of the same origin as claimed; genuine.
The experts confirmed it was an authentic signature.
adj. 2
Conforming to reality and therefore worthy of trust, reliance, or belief.
The report was completely authentic.
adj. 3
Designating a mode having the final as the lowest note.

Related words

Word family: authentically authenticate authentication authenticity
Phrases: authentic cadence

Choose the right word

Authentic or Genuine?

That is authentic which is true to the facts; that is genuine which is true to its own claims; as, authentic history; genuine money. A 'genuine' work is one written by the author whose name it bears; an 'authentic' work is one which relates truthfully the matters of which it treats.

J. C. Fernald, English Synonyms and Antonyms (1914)

Example sentences

original You seem to have lost sight of original objective.
actual James and Amanda were living an actual fairy tale.
genuine These letters have been acknowledged to be genuine.
legitimate Which prince is the legitimate heir to the throne?
reliable I wonder whether Tom and Mary are really reliable.
trustworthy He is a good fellow for sure, but not trustworthy.

Popularity over time

Word	1850 → 2019	Trend
authentic		rising
original		steady
actual		falling
genuine		steady
legitimate		steady
reliable		steady

Use in printed books, per decade from 1850 to 2019.

By length

4 letters: sure¹, real¹, true¹, pure¹
5 letters: pyore
6 letters: actual³, trusty²
7 letters: certain², genuine³, earnest², unfaked
8 letters: original⁴, received², accepted³, reliable⁴, credible³
9 letters: veritable⁴
10 letters: legitimate⁴
11 letters: trustworthy³
12 letters: authenticate⁴
13 letters: authoritative⁵, unadulterated⁶
14 letters: unquestionable⁵

The small number after each word is its number of syllables (actual³ = 3 syllables).

In other languages

Français: authentique
Italiano: autentico
Español: auténtico
Deutsch: authentisch
Català: autèntic