isochrone
C2Highly technical/specialist
Definition
Meaning
A line on a map connecting points where something occurs or arrives at the same time.
A curve in space or on a map representing equal time, either for travel or for the occurrence of an event (e.g., seismic wave arrival). Also used metaphorically for any phenomenon measured in equal time intervals.
Linguistics
Semantic Notes
Primarily a noun. While related adjectives exist ('isochronic', 'isochronal'), 'isochrone' itself is not used as an adjective in standard English. The concept is central to fields like cartography, transport planning, geology, and operations research.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage. Spelling and pronunciation are consistent.
Connotations
Equally technical and specialized in both varieties.
Frequency
Extremely rare in general discourse in both varieties, confined to technical contexts.
Vocabulary
Collocations
Grammar
Valency Patterns
The isochrone [VERB]...An isochrone of/for [NOUN PHRASE]Isochrones [VERB]...Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “[No common idioms for this highly technical term]”
Usage
Context Usage
Business
Used in logistics and retail site analysis to map customer accessibility within specific drive times.
Academic
Common in geography, geology (seismology), urban planning, and transport studies papers.
Everyday
Virtually never used.
Technical
The primary register. Used in GIS software, seismic interpretation, and transport modelling.
Examples
By Part of Speech
verb
British English
- [No standard verb use]
American English
- [No standard verb use]
adverb
British English
- [No adverb form]
American English
- [No adverb form]
adjective
British English
- [The adjective form is 'isochronic', e.g., 'The map displayed isochronic bands.']
American English
- [The adjective form is 'isochronic', e.g., 'The analysis used an isochronic approach.']
Examples
By CEFR Level
- [Too advanced for A2 level]
- [Too advanced for B1 level]
- The new bus route created a wider 30-minute isochrone around the city centre.
- Seismologists use isochrones to locate an earthquake's epicentre.
- The property developer's report featured isochrone maps showing 15-minute walk times from the proposed station.
- Isochrones drawn from the seismic refraction data revealed the depth to the bedrock layer.
Learning
Memory Aids
Mnemonic
Think 'ISO' (equal) + 'CHRONE' (time, as in 'chronology'). An ISOCHRONE shows where things happen at the SAME TIME.
Conceptual Metaphor
TIME AS SPACE (The abstract concept of time is mapped onto the concrete dimension of space through lines on a map).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'изохрона' (a correct technical translation). Avoid using 'синхронный' (synchronous), which refers to events coinciding in time, not lines of equal time.
Common Mistakes
- Mispronouncing as 'iso-chrone' (like 'chrome') instead of 'iso-crone'.
- Using it as an adjective (e.g., 'isochrone lines' is redundant; use 'isochronic lines').
- Confusing with 'isopleth' (a general line of equal value) or 'isotach' (line of equal speed).
Practice
Quiz
What is the core meaning of 'isochrone'?
FAQ
Frequently Asked Questions
No, it is a highly specialized technical term used almost exclusively in fields like geography, geology, and transport planning.
No. The correct adjective forms are 'isochronic' or 'isochronal'. 'Isochrone' is strictly a noun.
In many technical contexts, they are synonyms. However, 'isochron' is often preferred in geology (e.g., radioactive dating) and physics, while 'isochrone' is more common in cartography and transport.
In British English: /ˈaɪ.sə(ʊ).krəʊn/ (EYE-so-krone). In American English: /ˈaɪ.sə.kroʊn/ (EYE-so-krohn). The stress is on the first syllable.