Definitions of Pigging

The Various Meanings and Uses of the term “Pigging”.

Just out of interest, we’ve put together a list of definitions of the word pigging which you may (or may not) have come across.

HPS (whose website you are on) specialises in providing systems for other companies that process liquids. These systems use a technology called “pigging”. Unsurprisingly then, the vast majority of people that contact HPS or visit our website are interested in the type of technology that HPS provides, i.e. pigging systems, equipment and related services. In this sense, the term ‘pigging’ is being used to refer to an industrial process which recovers residual liquids from the inside of process pipe lines rather than wasting it.

However, while it’s common to use the word in reference to liquid product recovery systems, it also has other definitions and uses.  Because it has more than one meaning, sometimes people land on our website or social media pages looking for different types of activity or product which also go by the name pigging. Occasionally, they even send us emails or call us.

An Industrial Process for Recovering and Transferring Liquids

Lets clarify this definition first because it is the type of pigging referred to throughout the rest of this website. Rather than go in to detail about it here, you can get an overview by visiting our what is pigging web page, which will tell you all about it. If you want to find out more about HPS (and in case you were wondering, HPS stands for Hygienic Pigging industrial pigging system automation screenSystems), you can find out about our company, processes and equipment by taking a look at the About US section of this website, read some of our News and Blog articles about pigging or view our demonstration videos.

While it is a specialised process, even within this definition of pigging, there are different types and flavours. So here’s an article which tells you about the difference between pigging in processing applications and pigging in utility industries. And of course if you are thinking about implementing a product recovery system in your organisation, please get in touch with us.

Hopefully that’s clarified what pigging means with respect to the industrial processing of liquids. Now, here are some of the other meanings of the word pigging (in no particular order).

In Relation to Food

Probably the commonest use of the word outside of industrial processing, pigging is also used as a verb meaning to eat to excess or greedily devour food. It’s often followed by the word ‘out’ (‘pigging out’), meaning to eat a lot. For example, “we were pigging out at the all-you-can-eat restaurant”. It seems like this sense of the word is used widely throughout the English speaking world, unlike some of the following definitions which are more or less confined to certain areas.pigging speech bubble

A Mild Curse or Inoffensive Explanation

Sometimes the word pigging may be used in place of a more offensive explanation, swear word or expletive when someone is annoyed or frustrated. As far as we can tell this seems mainly confined to UK English, and is usually used in a light-hearted way, for example, “I just missed the pigging bus” rather than “I just missed the *!*#~*! bus”or “I just tripped over the pigging carpet”.

A Term for Hunting Feral Pigs

A controversial subject in Australia, where in some states pigging is used to describe the activity of hunting feral pigs in the bush, usually using dogs. This is either to control pig numbers, to hunt them for food or to hunt them for recreation. There’s a small industry developed around this type of pigging in Australia, including the supply of specialist knives, dogs, vehicles, rigs and other products.

This usage of the word seems pretty much confined to Australia, probably because that’s mainly where the activity takes place.

Using Ice Sludge to Clean Water and Sewage Pipes

Ice pigging is a process in which an ice slurry is pumped into a pipe and forced along inside in order to remove sediment and other unwanted deposits. In some sense it is related to industrial process pigging in that, rather than a solid pig, it uses ice. There are some big differences though. While ice pigging is suited to some larger-scale utility applications such as those used by water and sewage companies, it uses a lot of power to constantly produce ice, is expensive and cumbersome, and there’s always a problem with melting ice and water. Note that, although it’s been tried, ice pigging is not a viable alternative for  industrial process, hygienic and product recovery applications. Ice pigging does not lend itself to complex or automated pigging systems due to non-detectable, single use pigs, the inability to control ice slush, risk of contamination, melt and the need to dispose of the melting or melted ice.

Moulding Metalmetal pigs

Blocks of metal (usually iron or lead) produced by the smelting process are known as pigs.  The term pigging may be used in reference to the part of the smelting process which moulds the metal in to pigs. Like the process, the origins of the term ‘pig’ for a moulded metal block produced in this way go back a very long way.

Guinea-Pigging (1)

Testing something out. For example, “It’s raining, so I’m guinea-pigging this new jacket to see if it really is waterproof”. On a more serious note, when healthy humans take part in medical trials, drug studies, drug safety testing and so on, they’re said to be guinea-pigging.

Guinea-Pigging (2)guinea pigging

Spending time with one or more guinea pigs, the popular children’s and family pet. Generally more fun than taking part in medical trials (the other sort of guinea-pigging), but less lucrative.

A Type of Binding

A mainly US expression, a “pigging string” or “pig’ gin’” string is a small piece of rope used in some types rodeo to bind the legs of a calf after it’s been lassoed.

When a Female Pig Gives Birth

When a sow is giving birth to piglets, she may be said to be pigging.

Huddling Uppigs crowded together

When two or more people lay down and huddle together like piglets.

Crowding Together

When too many people get together in a space, usually in unpleasant, disorderly or unclean conditions, they can be said to be ‘pigging it’.

An Adult Activity

There is at least one other definition of pigging. However, as a company dedicated to helping other companies improve their processes through the use of industrial technology, it’s not appropriate to go in to the details here. Let’s just say there’s a definition of pigging which is based around particular types of activity usually performed in private between consenting adults. We don’t recommend you visit the types of website covering this area of ‘special interest’ while you are at work or using your  college or university computer system because, unless your company has a very liberal internet usage policy, they are probably not ‘work safe’. You get the drift.

Other Definitions of Piggingquestion mark

Have we missed anything?

If you have heard of other definitions of pigging which you think we should also include, please send an email to with the details and we will consider adding them (but remember we are a ‘family friendly’ website!).