As nouns the difference between terms and hydractinian
is that terms is while hydractinian is (biology) a marine hydroid of the genus (taxlink) or a closely-related genus.
terms
English
Noun
(head)
Statistics
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hydractinian
English
Noun
(
en noun)
(biology) A marine hydroid of the genus (taxlink) or a closely-related genus
Hypernyms
*hydractiniid
*hydrozoan
*cnidarian
*animal
*eukaryote
*organism