noun · 6 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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UK:/ˈsɪəɹəm/
UK:/ˈsiːɹəm/
Southern-England:Recorded audio is listed in the source snapshot.
US:/ˈsɪɹəm/
Canada:/ˈsiɹəm/
rhymes with (UK) -ɪəɹəm
rhymes with (US) -ɪɹəm
CMU ARPABET:S IH1 R AH0 M
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
noun
Meaning 1
Ellipsis of blood serum.
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
Blood serum used as a blood product, in the practice of medicine: blood serum from the tissues of immunized animals (human or nonhuman), containing antibodies and used to transfer immunity to another individual (human or nonhuman).
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Examples
Near-synonym: antiserum
Meaning relationships
Synonyms: antiserum
Antonyms: none provided
3
noun
Meaning 3
A watery liquid from animal tissue, especially one that moistens the surface of serous membranes or that is exuded by such membranes when they become inflamed, such as in edema or a blister.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
4
noun
Meaning 4
The watery portion of certain other animal fluids, such as milk; whey.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
5
noun
Meaning 5
A skincare product of varying consistencies with a high concentration of one or more active ingredients, for a targeted purpose, such as preventing acne, repairing sun damage, or moisturizing.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
6
noun
Meaning 6
an amber, watery fluid, rich in proteins, that separates out when blood coagulates
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: blood serum
Antonyms: none provided
Broader terms: liquid body substance, bodily fluid, body fluid, humor, humour
Narrower terms: antiserum, whey, milk whey
History
Etymology
Etymology tree Proto-Indo-European *ser- Proto-Indo-European *sér-o-der. Proto-Italic *serom Latin serumder. English serum From Latin serum (“whey”). Cognates include French sérum, Spanish suero, Italian siere, siero, Portuguese soro. Doublet of suero.
Across languages
Translations
58 source translations are retained for this English entry.