ENGLISH
REFERENCE

sera

n. plural-only
C2 Proficiency US //ˈsɪɹə// UK //sˈiəɹɐ// sera

n. the plural form of serum. It refers to the clear, liquid part of blood that remains after it has clotted, often used in medicine or science.

n. the plural of serum; refers to the clear, yellowish fluid that separates from blood during clotting. Often used in medical and biological contexts to describe fluids containing antibodies.


SIMPLE

The lab tested several sera for signs of the virus.

CONTEXTUAL

Researchers compared the immune responses across different animal sera to identify which species produced the strongest antibodies.

COMPLEX

The study required the collection of various sera from patients who had recovered from the infection to determine if their blood contained neutralizing proteins.

Synonyms
Usage

The plural form of 'serum'; takes a plural verb. While 'serums' is also acceptable in modern English, 'sera' remains the standard in scientific and academic writing.

Pitfall

The sera is being tested.The sera are being tested.Sera is the plural form of serum and requires a plural verb.

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