# periodic table

Pronunciation: say "peer-ee-OD-ik tay-buhl" US /ˌpɪɹiˈɑdɪk ˈteɪbəl/, UK /ˌpɪɹiˈɒdɪk ˈteɪb(ə)l/

## Noun

1. A chart of the chemical elements arranged in order of atomic number, so that elements with similar properties fall in the same column, or group.
   - Simple: A chart of all the chemical elements, set out so that similar elements are in the same column.
   - _Sodium and potassium share a column of the periodic table, and both react violently with water._
   - _Chemists predicted the properties of undiscovered elements from the gaps in the periodic table._

## Origin

The table is called "periodic" because it follows the periodic law: when the chemical elements are arranged in order of increasing atomic number, elements with similar properties recur at intervals.

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