Today, the government announced the extension of its definition of domestic violence to include "coercive control", and to apply when victims are aged 16-17. With a terrible inevitability, my Twitter feed immediately filled up with comments like "can parents now be arrested for withholding pocket money?" and the slightly less coherent: "Coercive control? Were [sic] do I start???!!!!" (Ooh, I don't know - by actually making some sort of argument?)

Some of the media did try to explain it properly. The BBC news explained in passing that this will not change the law. Various news updates have wrongly insisted that this is the "first time" that psychological abuse has included when in fact those very words have been right there all along, but most haven't stumbled into misrepresenting the move as allowing prosecutions that weren't possible before (except the Telegraph).

But without a fuller account of what the government definition is actually for, and the wider context of how domestic violence is addressed, there is little hope this won't be seen as the latest logic-defying conquest of the feminists. And if I'm quick, there's even a small chance I can get this posted before noted legal experts like George Galloway and Brendan O' Neill come along to offer their unique brand of clarification.

The first misconception to tackle is any suggestion that "coercive control" will now be a crime, and conversely that victims aged 16-17 weren't previously entitled to see their cases come to court. The definition is about government policy; it has no bearing on the law. This is because domestic violence is not a specific crime in this country, but is prosecuted using the same offences used for other forms of violence: primarily offences against the person such as common assault, ABH and GBH, and sexual offences- which are used for victims of any age.

Where a context of domestic violence is relevant in legal proceedings is around the edges of the actual charge; it helps establish that an incident may not be a one-off but part of a pattern of abuse. This is essential to help decide when it's in the public interest to prosecute, to flag up extra evidence like the victim's past medical records, and to inform sentencing, including protective measures like restraining orders. It defines the nature of the violence - but our lawmakers aren't so slack that violence itself wasn't already illegal.

And the purpose of the government's definition is far wider than enabling more effective prosecution after terrible things have already happened. It is also - arguably most importantly - about preventing violence and its escalation to homicide. When a single definition was introduced in 2004, it was the first time that a standard wording was used across all the agencies with a role in helping victims to identify abuse and access help - from the police to commissioners of support and refuge services to local government housing departments.

In other words, although it is no more than a paragraph in a range of obscure documents, it aims to ensure coordinated, consistent, transparent interventions for people at risk of serious harm. There can be little doubt that it has saved lives.

The addition of coercive control will make help available even earlier, in cases where physical violence is either rare or entirely absent so far, but there is a pattern of intimidation and power grabs designed to break down someone's social, financial and behavioural autonomy. It means these victims will not be turned away from services and, where the abuse does lead to a crime, the police and CPS know what they're dealing with. Including victims aged 16-17 is particularly important given that intimate partner relationships and even marriages before the age of 18 are hardly uncommon, and that the British Crime Survey shows 16-19 year olds are the age group most likely to suffer abuse from a partner. Previously, victims aged under 18 might have been either missed entirely, or categorised as suffering from child abuse and hence not referred to the right services.

If you've made it to the end of this rather boring attempt at an explanation, you've done better than not only the angrier parts of the Internet, but even the odd journalist. If you really want to show off, you could even read the announcement and original consultation.

But if you just want to get through the day without contributing to unhelpful misunderstandings, here's a short cut: this doesn't mean anyone can be prosecuted for things that were legal before. It does mean that the complex, escalating nature of domestic violence will be better understood, by victims themselves as well as the government, and that getting help just became a little easier.

Follow Ellie Cumbo on Twitter: www.twitter.com/elliecumbo