Phrase guide
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.
No pronunciation record was provided for this word.
noun
A function that is easy to compute in one direction but difficult to compute in the opposite direction (finding its inverse) without special information.
Definition source: English Wiktionary via Wiktextract
Topics: computing, cryptography, engineering, mathematics, natural-sciences, physical-sciences, sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
From the idea that it is easy to fall through a trapdoor but difficult to climb back out.
