# characteristic

Pronunciation: say "ka-ruhk-tuh-RIS-tik" US /ˌkæɹ(ə)ktəˈɹɪstɪk/, UK /ˌkæɹəktəˈɹɪstɪk/

## Noun

1. A distinguishing feature or quality of a person or thing, including an aspect of mental or physical behavior.
   - Simple: A quality or feature that makes one person or thing different from others.
   - _Stubbornness was a characteristic he inherited from his grandfather._
   - _Researchers listed several characteristics that set the new species apart from its relatives._
3. In mathematics, the whole-number portion of a logarithm, as distinct from its decimal part.
   - Simple: In math, the whole-number part of a logarithm.
   - _Students using log tables found the mantissa in the table and supplied the characteristic themselves._
   - _For any number between 1 and 10, the characteristic of its common logarithm is 0._
4. For a field or ring, the smallest positive number of copies of the multiplicative identity 1 that sum to the additive identity 0, or 0 if no positive number of copies does.
   - Simple: The smallest number of 1s that add up to 0 in a number system, or 0 if that never happens.
   - _Every finite field has a characteristic equal to some prime number._
   - _The rational numbers have characteristic 0, since no sum of 1s ever equals 0._
5. The identifying pattern of a navigational light, such as a lighthouse beacon (its color, rhythm, and sequence of flashes) by which mariners can recognize it.
   - Simple: The special pattern of color and flashes that a lighthouse light shows, so sailors can tell which lighthouse it is.
   - _Sailors identified the harbor light by its characteristic: a green flash every five seconds._
   - _The chart lists each beacon's characteristic so navigators can tell the lights apart at night._

## Adjective

2. Serving as a distinguishing feature of a particular person or thing; typical of them.
   - Simple: Typical of a person or thing and helping to show what makes them special.
   - _She answered with characteristic honesty, refusing to soften the bad news._
   - _A deep blue color is characteristic of glacial lakes._

## Origin

From Ancient Greek χαρακτηριστικός (kharaktēristikós), from χαρακτηρίζω (kharaktērízō, “to designate by a characteristic mark”), which comes from χαρακτήρ (kharaktḗr, “a mark, character”). By surface analysis, character + -istic.

Source: DictionaryAI, https://dictionaryai.com/define/characteristic (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).