indecipherable

/ˌɪndɪˈsaɪfərəbəl/

Say it: in-dih-SY-fuh-ruh-bul

1. adjective Impossible to read or make out because of being poorly written, faded, or otherwise unclear.
The doctor's signature was an indecipherable scrawl at the bottom of the form.
2. adjective Impossible to understand, interpret, or solve because of being mysterious, confusing, or enigmatic.
He gave an indecipherable smile, leaving her to guess what he was truly thinking.

📖 Seen in the wild

The ancient manuscript contained indecipherable symbols that puzzled historians for decades.
collected by @vocablast

✏️ indecipherable in a sentence

The ancient tablet was covered in an indecipherable script that has baffled historians for decades.
Due to the storm, the radio transmission from the ship was a wall of indecipherable static.
Her legal team found the new regulations to be dense and nearly indecipherable.
He muttered something indecipherable under his breath and walked away.
The artist's intentions remain indecipherable, which is precisely what makes the painting so compelling.
I received an indecipherable error message when the software crashed.
His motives for the sudden change in plans were completely indecipherable to his colleagues.

🔁 Synonyms & antonyms

illegible unintelligible inscrutable enigmatic incomprehensible unreadable cryptic obscure

illegible · refers specifically to handwriting or print that is physically unreadable.

unintelligible · often applies to spoken words or sounds that cannot be understood.

inscrutable · implies a mysterious quality that resists interpretation, often used for expressions or motives.

enigmatic · stresses a puzzling or baffling quality that makes something hard to figure out.

Opposites: decipherable, legible, clear, comprehensible, intelligible

🌱 Where it comes from

The word is a straightforward construction from the 17th century. It combines the Latin-derived prefix 'in-', meaning 'not', with the verb 'decipher' and the suffix '-able'. 'Decipher' itself comes from Old French for 'un-coding', as a 'cipher' was a secret code or the number zero.

🧩 How it's used

Common patterns:

indecipherable handwritingindecipherable scrawlindecipherable codeindecipherable messageindecipherable jargonindecipherable expression

Indecipherable has two main uses: literally for things that can't be read (like a faded manuscript) and figuratively for things that can't be understood (like a complex legal document or a mysterious smile). Be careful not to confuse it with 'illegible'. Something can be perfectly legible, with clear, crisp typing, but still be indecipherable if it's full of jargon or nonsense. Illegible only describes the physical clarity of the text.

Word family: decipher, decipherable, cipher

💬 Quick answers

What does indecipherable mean?

It means something is impossible to read or understand, either because it's physically unclear, like bad handwriting, or because it's conceptually confusing or mysterious, like a secret code.

What's the difference between indecipherable and illegible?

Illegible specifically refers to writing or print that is physically difficult to read. Indecipherable is broader: it can mean illegible, but it can also describe something that is impossible to understand or interpret, even if it is perfectly clear to see.

Can a person be indecipherable?

While you can describe a person as indecipherable, it's more common to describe their expression, motives, or speech that way. It means they are mysterious and difficult to understand.

Is indecipherable a formal word?

Indecipherable is a standard, neutral word suitable for most contexts, including formal and academic writing. In very casual speech, you might use a simpler word like 'unreadable' or 'confusing'.

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