cologarithm: meaning, definition, pronunciation and examples
Very LowTechnical/Historical
Quick answer
What does “cologarithm” mean?
The logarithm of the reciprocal of a number.
Audio
Pronunciation
Definition
Meaning and Definition
The logarithm of the reciprocal of a number; specifically, the negative of a logarithm.
In mathematics, particularly in logarithmic calculations and slide rule usage, the cologarithm of x is log(1/x) or -log(x). It was used historically to simplify computations involving division by allowing subtraction instead.
Dialectal Variation
British vs American Usage
Differences
No significant regional differences in meaning or usage. The term is equally obscure and technical in both varieties.
Connotations
Connotes historical or very specialised technical mathematics.
Frequency
Extremely rare in both varieties, found almost exclusively in historical mathematical texts or discussions of computational history.
Grammar
How to Use “cologarithm” in a Sentence
the cologarithm of [NUMBER]to find/take/calculate the cologarithmVocabulary
Collocations
Examples
Examples of “cologarithm” in a Sentence
verb
British English
- To cologarithm the value, simply reverse the sign.
- One would cologarithm the divisor before proceeding.
American English
- You need to cologarithm that number for the next step.
- The process required cologarithming the result.
adverb
British English
- The operation was performed cologarithmically.
- He computed it cologarithmically using the tables.
American English
- The value was derived cologarithmically to save steps.
- She worked cologarithmically to avoid division.
adjective
British English
- The cologarithmic scale was printed on the slide rule.
- He referred to the cologarithmic tables.
American English
- A cologarithmic function simplifies the division operation.
- The cologarithmic method is historically interesting.
Usage
Meaning in Context
Business
Not used.
Academic
Used only in historical discussions of mathematics or very specialised theoretical contexts.
Everyday
Never used.
Technical
Used rarely in specific mathematical or engineering history contexts.
Vocabulary
Synonyms of “cologarithm”
Strong
Neutral
Weak
Vocabulary
Antonyms of “cologarithm”
Watch out
Common Mistakes When Using “cologarithm”
- Confusing it with a type of logarithm rather than an operation on a logarithm.
- Using it in modern computational contexts where it is obsolete.
FAQ
Frequently Asked Questions
No, it is an obsolete term from the era of manual logarithmic calculation with slide rules and tables. Modern computers and calculators perform division directly.
Its purpose was to convert a division problem into a subtraction problem, as dividing by x is equivalent to multiplying by 1/x, whose logarithm is the negative of log(x) - the cologarithm.
Yes, though extremely rare, it can be used verbally (e.g., 'to cologarithm a value') meaning to take the cologarithm of it.
No, in this context, the prefix 'co-' is short for 'complementary' or is used to indicate the negative or reciprocal relationship to the logarithm.
The logarithm of the reciprocal of a number.
Cologarithm is usually technical/historical in register.
Cologarithm: in British English it is pronounced /ˌkəʊˈlɒɡ.ə.rɪ.ðəm/, and in American English it is pronounced /ˌkoʊˈlɑː.ɡə.rɪ.ðəm/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
COlogarithm is the COmplement (or negative) of a LOGarithm.
Conceptual Metaphor
A mathematical mirror image; flipping the sign.
Practice
Quiz
What is the cologarithm of 100 (assuming base 10)?