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.
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noun
The motion of some hypothetical device that continues forever with no external input of energy, in violation of the laws of thermodynamics.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
Topics: natural-sciences, physical-sciences, physics
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
motion that continues indefinitely without any external source of energy; impossible in practice because of friction
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
Broader terms: motion
History
No etymology was provided for this word.
Across languages
6 source translations are retained for this English entry.
