inf
Abbreviation with 5 meanings
| Stands for | Infimum |
|---|---|
| Meanings | 5 |
| Categories | Units & Measurements, Writing & Everyday |
| Also written | inf. |
inf has five meanings. The most common are Infimum (math) and Infinity (in computing) (math); it can also stand for Infinitive, Informal and Infant.
Meanings of inf at a glance
| # | inf stands for | Context |
|---|---|---|
| 1 | Infimum | Units & Measurements › Math |
| 2 | Infinity (in computing) | Units & Measurements › Math |
| 3 | Infinitive | Writing & Everyday › Grammar and Dictionary |
| 4 | Informal | Writing & Everyday › Grammar and Dictionary |
| 5 | Infant | Writing & Everyday › Genealogy |
1. Infimum
Units & Measurements · Math Abbreviations
The greatest lower bound of a set: the largest number less than or equal to every element. The infimum of the positive real numbers is 0, even though 0 itself is not positive.
Example: inf{1/n : n ≥ 1} = 0.
Every nonempty set of reals that is bounded below has an infimum, mirroring the supremum. When the infimum is attained it equals the minimum. Analysis texts use lim inf and lim sup to describe the eventual lower and upper bounds of a sequence.
2. Infinity (in computing)
Units & Measurements · Math Abbreviations
The representation of infinity in floating-point arithmetic and program output, produced for example by overflow or division by zero in many numeric libraries. The IEEE 754 standard defines positive and negative infinity as special values.
Example: Dividing by zero in NumPy returns inf along with a runtime warning.
Python writes float('inf'), JavaScript uses Infinity, and spreadsheets typically show an error instead. Every comparison treats inf as larger than any finite number, while inf − inf gives NaN (not a number). Algorithms often initialize a "best so far" distance to inf.
3. Infinitive (inf.)
Writing & Everyday · Grammar and Dictionary Abbreviations
Grammatical label for the base form of a verb, often preceded by "to," as in "to run" or "to be." Grammars and language textbooks use it when describing verb patterns.
Example: After "want," use the inf. with to: "I want to leave," not "I want leaving."
English distinguishes the to-infinitive ("to go") from the bare infinitive ("go"), used after modal verbs such as "can." The supposed rule against split infinitives ("to boldly go") is rejected by most modern usage authorities, including Fowler and Merriam-Webster. In genealogy, inf. may instead mean an infant.
4. Informal (inf.)
Writing & Everyday · Grammar and Dictionary Abbreviations
Register label marking a word or sense as suited to casual speech and writing rather than formal contexts. Compact and bilingual dictionaries use it to save space where others print "informal" or colloq.
Example: whopping (adj.) inf. very large: "a whopping $2 million for a parking space"
The Oxford and Cambridge learner's dictionaries print "informal" in full. The label belongs to a set of register markers that also includes formal, slang, literary and colloquial. In grammar texts, inf. more often means "infinitive," so readers should check the dictionary's list of abbreviations.
5. Infant (inf.)
Writing & Everyday · Genealogy Abbreviations
Notes that a child died in infancy, or identifies an unnamed baby, in genealogies and burial records, as in "d. inf." or "inf. son of John Hale."
Example: Gravestone: "Inf. dau. of Thomas and Ann Wright, d. 1852, aged 3 weeks."
High infant mortality in past centuries means many family trees include babies recorded only in burial registers. Infants who died before baptism sometimes appear without names. In grammar, inf. means infinitive or informal, so context tells which is meant.
Related abbreviations
More math abbreviations
- HCF – Highest common factor
- HL – Hypotenuse-Leg (congruence)
- iff – If and only if
- Im – Imaginary part
- IVT – Intermediate value theorem
- K – Thousand
- ker – Kernel
- lb – Binary logarithm
See all 91 math abbreviations →