What does indecipherable mean?
Indecipherable describes something that cannot be read, decoded, or interpreted. The word is especially common for handwriting that is too unclear to decipher, but it can also apply to encrypted messages, unfamiliar symbols, ancient inscriptions, signals, and deliberately obscure language. Its force comes from combining the ordinary word decipher, meaning to determine the meaning of something, with the idea of inability. In ordinary use, an indecipherable note may simply be written too poorly to read, while an indecipherable code may have been intentionally protected. Although illegible is often interchangeable in discussions of writing, indecipherable is broader because it can describe anything whose meaning remains hidden. The word is useful when describing difficulty of interpretation in formal, technical, or literary contexts.
adjectiveIncapable of being read, understood, or interpreted. It is most commonly used of writing, symbols, messages, and signals whose meaning cannot be determined.
- Impossible to read, decode, or interpret.
"The note was covered in indecipherable handwriting, so nobody could determine who had written it."
"The ancient inscription remained indecipherable despite years of study."
"She tried several passwords, but the symbols on the device were indecipherable."
Indecipherable is built from the idea of something that simply cannot be deciphered: the message may be there, but its meaning is locked away.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does indecipherable come from?
Indecipherable is formed from the prefix in-, meaning not, combined with decipher and the suffix -able, meaning capable of being. Decipher itself comes from French déchiffrer, from de-, meaning un-, and chiffre, meaning cipher, with the latter borrowed from Arabic sifr, meaning zero or empty, originally referring to a calculation in a blank or zeroed calculating board. Related English forms include decipher, decipherer, and decipherment, all belonging to the same semantic family of reading or working out meaning.
How indecipherable is actually used
Usually formal and descriptive. It is common in writing about handwriting, encrypted messages, codes, inscriptions, and signals, and it can suggest either accidental difficulty or deliberate concealment.
Easily confused with indecipherable
Illegible usually describes writing or print that cannot be read, whereas indecipherable is broader and can refer to a message, code, or symbol whose meaning cannot be interpreted.
Inscrutable often suggests that something is deliberately mysterious or difficult to understand, while indecipherable focuses on the practical impossibility of decoding or interpreting it.