Remember when 'Sugar Daddy' was just a Tom Jones hit and its offspring counterpart, 'Sugar Baby', was merely a Bob Dylan track?

Oh how the times they are a-changin’.

It now describes a very specific kind of relationship in which a young "sugar baby" receives funding from an older sugar daddy, or in rarer cases a sugar mummy.

But the arrangement isn't always as straightforward as you'd imagine - and there's an entire spectrum of arrangements, all couched in surprisingly opaque language.

While women are encouraged to be sugar "mamas" on a few platforms, the general assumption is that it's men who'll be coughing up cash.

However, what the older sugar parent receives in exchange for their "generosity" is a very murky matter indeed.

It’s a transaction that is shrouded in ambiguity to the extent that it has a different definition on every sugar dating platform.

For example, on the Sugarmodels app, sugar daddies are matched with sugar babies whom they can "pamper".

On Richmeetsbeautiful.com, a sugar baby is expected to simply be available for her sugar daddy and is described as "sweetening his spare time and sharing his luxury lifestyle”.

Meanwhile, on SeekingArrangement, a sugar baby is guided towards finding "a mentor” but is confusingly also told that he/she will be “dating experienced men”.

Describing the nature of their services to The Independent, a spokesperson explained that these relationships are "mutually beneficial".

"Men get the companionship of a young, vibrant woman who is ok with the fact that this relationship might not end in marriage," they added.

"They get all the perks of a traditional relationship without the hidden agendas and baggage that typically accompanies a relationship.

"This style of dating isn’t for for everyone, but it does help cut through the noise when trying to find someone who’s like-minded."

While the sugar baby’s "perks" remain distinctively undefined, the sugar parent’s role is as clear as day.

In order to create an account on most sugar baby sites or apps, you're asked to define which role you'd like to take before almost immediately having to explicitly state your financial means and requirements.

As a sugar baby, you have to state how much money you’re looking for by way of a bracket, on some platforms this ranges up to more than $10,000 (£7,400) per month.

As a sugar parent, you’re required to state your overall net worth and your annual income - think of it as an inappropriate LinkedIn profile.

Once the financial bits are sorted, you can start to build your profile.

At a first glance, the process is not too dissimilar from that of a typical dating site, with run-of-the-mill info like height, eye colour, occupation etc.

However, eyebrows might raise when you're prompted to rate the level of your sex drive, explain what turns you on and state whether or not you have a “secret love nest “ – not quite so smoke and mirrors after all.

On RichMeetsBeautiful, you’re also asked to state your relationship status – you didn’t think sugarfolk were monogamous did you?

Once you’ve got your profile set up, it’s time to find your sugary partner, who may or may not be the next Silicon Valley tycoon, or at least, that’s what their profiles imply.

For example, on one website we came across a 30-year-old businessman from LA with a claimed net worth of £6m, a middle-aged Florida-based entrepreneur worth £30m and an athlete in his 20s from Berlin worth £60m.

Whether they are actual human beings or mere Sim-like characters dreamt up by pre-pubescent teenagers in their bedrooms remains unclear.

Regardless of the small print, these men present themselves as very wealthy indeed, often having words like “rich”, “finest” and “impressive” in their profile – just in case you didn’t get the memo that these guys have got dollar bills.

Unlike other dating sites or apps, there is no match-making algorithm; users can speak to one another freely without having to consent first.

While helpful, the guise of ambiguity does little to cushion the fact that any prospective couples will be matched on financial compatibility i.e. how much a sugar baby is looking to "earn" and how much a sugar parent is willing to pay.

With things like sex drive and turn ons listed on people's profiles, the sites are synonymous with intimacy.

So, there are two people, there's definitely money and there may or may not be sex.

In that case, how do these sites dissociate themselves from prostitution services?

Crucially, none of the sugar baby services I encountered facilitate transactions between members - the expectation is that they will be conducted privately.

But even if the websites did advocate such a digitalised brothel-like service, prostitution is not illegal in England and Wales.

"If consenting adults come to an agreement between themselves to pay for sex, no offence has taken place,” explains Zita Spencer, a solicitor at Olliers.

However, that’s not to say there aren’t regulations imposed surrounding the act of prostitution.

For example, it would be on offence to persistently solicit/loiter in a public place for the purposes of prostitution, Spencer told The Independent.

"The focus of the law over the years has been on preventing nuisance to the public and other offences often associated with prostitution such as drug abuse, exploitation and trafficking,” she explained.

It’s also worth noting that sugar baby websites and apps go to great lengths to present themselves as dating services.

However niche their matchmaking may be, they promote a service which suggests matches based on compatibility and any fee paid to join the website is for that matchmaking service only.