Meaning & use
serum
Last updated
Meanings
nouncountable or uncountablemedical
The pale yellow liquid part of blood that remains once the blood cells and the clotting substances are removed.
Grammar: Uncountable for the substance: blood serum; countable for types: sera or serums.
Patterns
- serum from something
The lab separated the serum from the blood sample.
Doctors measured the level of sugar in the patient's serum.
Antibodies can be found in the serum.
nouncountable or uncountablemedicalold-fashioned
A liquid taken from the blood of an immune animal or person and injected to protect against or treat a disease.
Grammar: The plural is sera or serums.
Patterns
- a serum against something
Scientists once made a serum against snake venom from horse blood.
The village received a serum to treat the outbreak.
nouncountable or uncountable
A light, concentrated liquid for the skin, applied before moisturizer to treat dryness, lines or other concerns.
Grammar: Often countable in shops: three different serums.
Patterns
- a serum for something
She applies a vitamin C serum every morning.
This serum is gentle enough for sensitive skin.
The store sells a hydrating serum for dry winters.
Word forms
| plural | sera |
|---|---|
| plural (variant) | serums |
Common combinations
- blood serum
- Blood serum is tested for signs of infection.
- face serum
- She dabbed a face serum onto her cheeks.
- vitamin C serum
- A vitamin C serum is popular for brightening skin.
- serum level
- The doctor checked the serum level of iron.
- serum sample
- A serum sample was sent to the laboratory.
Synonyms and how they differ
- plasma
- Plasma is the liquid in blood that still contains clotting substances, while serum is what remains after clotting.
- antiserum
- Antiserum is a serum containing antibodies used for treatment, so it is narrower than serum.
- essence
- Essence is a skincare product that is lighter and watery, whereas a skin serum is usually thicker and more concentrated.
- lotion
- Lotion is a heavier, thicker moisturizing product, while a serum is lighter and applied first.
Word family
- serology noun
- the study of serum and antibody reactions
- serous adjective
- like or containing serum, as in a watery fluid
- seropositive adjective
- showing antibodies in a blood test
- antiserum noun
- serum containing antibodies against a disease
Commonly confused: serum or plasma? serum or serene?
serum vs plasma
Plasma is the blood fluid before clotting and still contains clotting proteins, while serum is what is left afterwards.
serum vs serene
Serene means calm and peaceful and is unrelated to the fluid.
Practice
The laboratory separated the clear ______ from the cells in the blood sample.
Choose one answer.
Serum is the clear fluid part of blood. Sermon, severity and sequel are real words that look similar but have nothing to do with blood.
Make it your own
Write a sentence using “serum”, then check it and compare it with the examples above.