noun · 2 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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Received-Pronunciation:/ˌɹeɪ.di.ə(ʊ)ˈlɛəɹi.ən/
General-American:/ˌɹeɪ.di.oʊˈlɛɹi.ən/
General-American:/ˌɹeɪ.di.əˈ-/
rhymes with -ɛəɹiən
1
noun
Meaning 1
Any of many marine amoeboid protozoa, of subclass Radiolaria, having filamentous pseudopodia; they have intricate silica skeletons.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
protozoa with amoeba-like bodies and radiating filamentous pseudopods
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
Broader terms: actinopod
History
Etymology
Etymology tree Translingual Radiolaria Proto-Indo-European *-nós Proto-Italic *-nos Latin -nus Latin -ānus Old French -ainder. Middle English -an English -an English radiolarian From Translingual Radiolaria + English -an.
Across languages
Translations
13 source translations are retained for this English entry.