actinide

/ˈæktɪnaɪd/

actinide noun: any of the 15 radioactive elements of the periodic table from actinium to lawrencium that are positioned under the lanthanides, to which they have similar chemistry.

Noun

actinide (plural actinides)

Any of the 15 radioactive elements of the periodic table from actinium to lawrencium that are positioned under the lanthanides, to which they have similar chemistry.
Any of the 14 elements from actinium to nobelium (lawrencium is excluded by some authors as it is a d-block rather than an f-block element).
(dated) Any of the 14 elements from thorium to lawrencium (actinium having been mistakenly excluded because it was thought to be a d-block element in the past).

actinide meaning in Hindi and Tamil

actinide in Hindi

one of a group of radioactive elements: एजातेय ejātey

actinide in Tamil

அட்டினவன்ன

Forms of actinide

plural	actinides

Origin of actinide

From actin- + -ide.

Words formed from actinide

Questions about actinide

What does actinide mean?: Actinide means any of the 15 radioactive elements of the periodic table from actinium to lawrencium that are positioned under the lanthanides, to which they have similar chemistry.
What is actinide in Hindi?: Actinide in Hindi is एजातेय (ejātey). See Actinide meaning in Hindi.
What part of speech is actinide?: Actinide is a noun.
How do you pronounce actinide?: Actinide is pronounced /ˈæktɪnaɪd/.
What is the plural of actinide?: The plural of actinide is actinides.

Words near actinide in the dictionary

Adapted from Wiktionary: actinide (page history and authors); actinide (Tamil Wiktionary) (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated: 2026-09-02

Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Vealhurl-actinide.wav.

Cite this entry: “actinide.” Word.ws, https://word.ws/actinide. Based on Wiktionary, CC BY-SA 4.0.