activation energy
noun
Simple meaning
The energy required to initiate a reaction.
Pronunciation
Say it like this:
aktuhvayshuhnehnerjeeSay the bold part a little louder.
IPA pronunciation (US)
æktəˈveɪʃəˈnɛnɚdʒi
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
physical chemistryphysics
The energy required to initiate a reaction. For example, the flame from the fuse of a firecracker provides a small initial amount of energy, after which the explosive reaction proceeds by itself, releasing a considerably larger quantity of energy. A small push given to a stable but top-heavy object may cause it to fall over; the potential energy released during the fall was present in the system all along but could not be realized as long as the object was upright and balanced.
Word Aura™
How this word commonly comes across.
This meaning: (physical chemistry, physics) The energy required to initiate a reaction. For example, the flame from the fuse of a firecracker provides a small initial amount of energy, after which the explosive reaction proceeds by itself, releasing a considerably larger quantity of energy. A small push given to a stable but top-heavy object may cause it to fall over; the potential energy released during the fall was present in the system all along but could not be realized as long as the object was upright and balanced.
Used this way, activation energy is a specialist word that usually carries little praise or criticism of its own. It stays understated rather than dramatic. This is a scientific use: it names something precisely within a field of study, so it appears in research and teaching more than in conversation.
- Emotional tone
- Neutral
- Formality
- Specialist/technical
- Intensity
- Mild
- How common
- Specialized
- Connotation
- Clinical and technical
- Usage feel
- Technical and specialized
Where it naturally appears
- Science
- Academic writing
- Technical/specialist writing
Usage note
In general conversation this sense usually needs explaining — outside its field, people reach for a plainer word.
Word Aura describes common impressions, not a measurement. Tone changes with sentence, speaker, relationship and situation.
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