I know this topic is unlikely to pique any native speaker's curiosity, but bear with me, I am trying to learn the difference between froth, foam, lather and suds.

I feel these terms are not always interchangeable even though they mean more or less the same. There isn't anything called shaving froth. Yet, I can't explain clearly the difference between froth, foam, lather and suds.

I would appreciate if someone could enlighten me.

(Edit) ODO definitions:

  1. Froth – a mass of small bubbles in liquid caused by agitation, fermentation, or salivating.
  2. Foam – a mass of small bubbles formed on or in liquid, typically by agitation or fermentation.
  3. Lather – a frothy white mass of bubbles produced by soap, washing powder, etc. when mixed with water.
  4. Suds – froth made from soap and water.
  • You should probably consider adding spume to your list of frothy, foamy terms.
    – tchrist
    Commented Jan 4, 2013 at 13:15
  • You're right that these are all nominal synonyms. But their collocations are different enough. Didbtheir dictionary definitions show those nuances? Maybe you could add those to your question.
    – Mitch
    Commented Jan 4, 2013 at 13:17
  • Froth ain't right. Shaving cream is the standard collocation. Gillette Foamy (R) is a brand of shaving cream. Froth, foam, & lather is what you get "when soap or some other detergent is agitated with or in water" (MW3UDE). Suds is foam or froth or beer.
    – user21497
    Commented Jan 4, 2013 at 13:24
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    Although all the terms describe suspended bubbles, the difference is where they are/how they were formed, as indicated by the definitions. There may well be regional differences at work here, too. Shaving foam is right for the UK. Cream is what produces the foam. Beer has froth. Spume is used solely for sea-foam.
    – Andrew Leach
    Commented Jan 4, 2013 at 13:29
  • 2
    @AndrewLeach Interesting that spume originates from the Italian spuma which gives us the spumante in sparkling wine. Commented Jan 4, 2013 at 16:03

4 Answers 4


What follows may be regional to the mid-western US version of English.

"Lather" and "suds" are reserved for mixtures of soap and water. "Suds" usually implies larger bubbles whereas "lather" has small or no bubbles. You will find "suds" in your laundry wash tub but not "lather." Your shampoo bottle instructs you to "lather, rinse, repeat," but the soapy substance on your head can be described as either "lather" or "suds." Shaving cream makes "lather," which is rarely, if ever, described as "suds."

"Foam" usually implies a certain permanence to the material whereas the bubbles found in "froth" usually, but not always, dissipate fairly quickly. "Foam" also implies larger bubbles than "froth." Whipped cream can be described as "frothy," but without having noticeable air bubbles it would probably not be described as "foamy." "Frothy" can also be used to describe churning water, like you would find at the bottom of a waterfall or in a boiling pot.

  • 2
    Being from the midwest, I'm almost with you - but not quite 100%: Though shampoo says lather, I'm taking that to be the verb - but what appears on my head is more sudsy. Everything else is pretty consistent with my usage. +1 Commented Jan 4, 2013 at 19:00
  • Makes sense to me, too. +1 and accept.
    – user32480
    Commented Jan 5, 2013 at 2:35
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    As a midwesterner I object that beer can have suds.
    – MetaEd
    Commented Jan 6, 2013 at 0:12
  • Even as a tt I object that beer can have suds.
    – Kris
    Commented Jan 6, 2013 at 11:12
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    Perhaps this sounds like a technicality, but I might be persuaded to agree that "suds" is reserved for soap and water, in that using "suds" to describe a beer head would be regarded as slang. (As a side note, NOAD defines suds as "short for soapsuds" and then adds a subdefinition of "beer", but that secondary meaning is labeled as "informal".)
    – J.R.
    Commented Jan 7, 2013 at 1:01

For these four words, they either share large parts of their definitions or refer to each other.

Where they are different is in their usual contexts and/or phrases:

  • foam is if anything the most general and the hypernym of the set. It can refer to a liquid

    sea foam

    for the foam that is created at the crests of waves or

    foaming at the mouth

    a foam made of saliva, or a solidified form like a

    foam cushion

  • froth is more likely to be related to food like a

    frothy meringue

  • lather is mostly related to use of soap, thicker than suds.

    Lather. Rinse. Repeat

    are the instructions for when one creates a lather with shampoo in one's hair. But also, horse sweat as in:

    beat a horse into a lather

  • suds are lighter (larger bubbles) than a lather, and often associated with soap for cleaning both personal and laundry.

    soap suds


Froth is typically reserved for beverages, though there are times when it is used to describe bubbles from saliva. Generally speaking though, it is the most limited word on the list in terms of common usage, and it is most often associated with beverages (or used in metaphors, in lieu of the "icing on the cake").

Foam, on the other hand, is probably the most commonly used word on the list, as its meaning has grown to cover all sorts of ideas: polystyrene (Styrofoam), froth, etc. Andrew stated in the comments that "shaving foam" is the correct term in the UK, but I believe in the US there's a tendency to avoid "foam" for all soap and cream related purposes - we would simply refer to it as "shaving cream". However, foam is the most general term, so no matter what, it can apply (in the US) to almost any bubbly substance. You can't go wrong with foam!

"Lather" is not only a noun, but a verb. According to the Cambridge Dictionary, it means "to produce lather from a soap, or to cover something in lather." As much as I hate to use circle definitions, I typically would describe "lather" as the product of "lathering". If you rub soap against your hands or skin, you are producing lather. It has a connotation of "cleaning", and it is almost always associated with "soap".

Suds is a more common term, but almost exactly the same as lather - however, while lather carries a meaning of "the product of rubbing soap against something", suds is just soapy bubbles, and it is always soap and water.

tl;dr: use foam.

  • Lather is also something you see in connection with horses. It's a foam of sweat.
    – MetaEd
    Commented Jan 6, 2013 at 0:13

I read that each word originates from a different language. Suds comes from Dutch. Foam comes from Latin.

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    This would be improved as an answer if you could include a reference for each of these. Commented Dec 5, 2019 at 14:10