1

actinoid

adjective ac·ti·noid \ ˈak-tə-ˌnȯid \

Definition of actinoid

1 :resembling a ray especially of a radially symmetrical animal
2 :exhibiting radial symmetry

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Origin and Etymology of actinoid

actin(ia) +2-oid (probably afteractinoida oractinoidea)


2

actinoid

noun ac·ti·noid \ ˈak-tə-ˌnȯid \

Definition of actinoid

plural actinoids
chemistry
:actinide
  • The actinoid elements (or actinides; An) constitute a series of 14 elements which are formed by the progressive filling of the 5f electron shell and follow actinium in the periodic table (atomic numbers 90-103).
  • —Mirtat BouroushianElectrochemistry of Metal Chalcogenides2010

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Origin and Etymology of actinoid


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