rotameter
Very Low / TechnicalFormal, Technical, Scientific
Definition
Meaning
A device for measuring the flow rate of a fluid (typically a gas or liquid) in a closed tube, consisting of a tapered vertical tube with a float that rises to a height corresponding to the flow rate.
In broader technical contexts, any variable-area flowmeter using the same float-in-tapered-tube principle. The term can sometimes be used by analogy for any simple mechanical indicator of rate or volume.
Linguistics
Semantic Notes
The word is a compound of 'rota-' (related to rotation) and '-meter' (measuring device), though modern rotameters often rely on vertical float movement, not necessarily rotation. It is a highly specific technical term with no everyday metaphorical use.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. Spelling is consistent.
Connotations
Purely technical, with no regional connotations.
Frequency
Equally rare and specialized in both dialects, confined to engineering, laboratory, and industrial contexts.
Vocabulary
Collocations
Grammar
Valency Patterns
The rotameter measures [fluid name] flow.A rotameter was installed in [system/line name].[Number] l/min is indicated on the rotameter.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Extremely rare; might appear in procurement specifications for industrial equipment.
Academic
Used in engineering, physics, and chemical engineering papers and textbooks describing fluid dynamics or experimental setups.
Everyday
Virtually never used.
Technical
The primary domain. Common in manuals, process diagrams, and technical discussions in fields like pneumatics, hydraulics, and process engineering.
Examples
By Part of Speech
adjective
British English
- The rotameter reading was stable.
- A rotameter-type sensor was chosen.
American English
- The rotameter calibration is off.
- We need a rotameter-style flow indicator.
Examples
By CEFR Level
- The technician checked the rotameter to see the gas flow.
- For accurate measurement of the coolant, a calibrated rotameter was installed in the return line.
- The experimental apparatus featured a precision rotameter to monitor the argon flow rate, with the float's height being recorded digitally.
Learning
Memory Aids
Mnemonic
Think: ROTAting (or RIsing) flOAT + METER = ROTAMETER, a meter with a float that rises.
Conceptual Metaphor
FLOW IS HEIGHT / RATE IS POSITION (The rate of flow is conceptualised as the vertical position of the float within the tube).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid translating as "ротаметр" without context; it is a highly technical loanword. The descriptive term "расходомер с поплавком" (float flowmeter) may be clearer.
Common Mistakes
- Misspelling as 'rotometer' or 'rheometer' (a different instrument).
- Using it as a general term for any meter or gauge.
- Assuming it measures rotation speed rather than flow rate.
Practice
Quiz
In which field is the term 'rotameter' most commonly used?
FAQ
Frequently Asked Questions
It measures volumetric flow rate (e.g., litres per minute), not speed or total volume.
No, it must be calibrated for a specific fluid's properties (density, viscosity). Using it for a different fluid gives inaccurate readings.
No, it is a generic technical term, though it may be trademarked in specific jurisdictions for certain products.
A tapered transparent tube with a float inside that rises with increasing flow.