Meaning & use
SLS
Last updated
Meanings
abbreviationuncountablechemistry
A chemical added to soaps, shampoos, and toothpaste to make them foam and lift dirt.
Grammar: Used like a substance name; no plural and no article before it in general use.
Patterns
- contain SLS
- SLS-free
- a product with SLS
This shampoo contains SLS, which is why it lathers so quickly.
Many people with sensitive scalps choose toothpaste that is free of SLS.
The label lists SLS as the second ingredient.
abbreviationpropertechnical
The large rocket built by NASA to carry people and cargo beyond Earth orbit.
Grammar: Treated as a name: no article, and usually written with the letters SLS.
Patterns
- the SLS rocket
- launch on SLS
NASA plans to send astronauts to the Moon using the SLS.
The first SLS flight carried an uncrewed capsule around the Moon.
Common combinations
- SLS-free
- She switched to an SLS-free shampoo to avoid irritation.
- contain SLS
- Most foaming face washes contain SLS.
- the SLS rocket
- The SLS rocket stood on the launch pad for weeks.
- sodium lauryl sulfate (SLS)
- The full name, sodium lauryl sulfate (SLS), appears on the back of the bottle.
Synonyms and how they differ
- sodium lauryl sulfate
- The full chemical name; use it in formal or technical writing, while SLS is the everyday short form.
- surfactant
- A broader term for any substance that helps water lift grease; SLS is one kind of surfactant.
Commonly confused: SLS or SLES?
SLS vs SLES
SLES is sodium laureth sulfate, a milder relative often used in the same products; it is a different chemical from SLS.
Practice
In a shampoo advertisement, what does SLS most likely mean?
Choose one answer.
In beauty and household products, SLS stands for the foaming agent sodium lauryl sulfate. The NASA rocket is also called SLS, but it would not appear in a shampoo ad.
Make it your own
Write a sentence using “SLS”, then check it and compare it with the examples above.