There's a certain word that some people use to refer to women, and it really gets on feminist's collective nerves.
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The problem is, it's usually not meant to be derogatory, but the meaning behind it, kind of is.
We're talking about people referring to women (any female over the age of 18) as 'girls.'
Big Bang Theory star Mayim Bialik has hit out at this commonplace term for women in a recent Facebook video, and we're 100 per cent with her.
The 41-year-old actress, who also has a doctorate in Neuroscience, tells viewers "I'm going to be annoying," as she launches into her four minute explanation of what we're really saying when we call women 'girls.'
Many of you at home are probably eye-rolling right now, wondering why yet another word has been struck off by the PC brigade. But what Mayim says really makes sense, if you give her a chance to explain.
Talking through an anecdote where two of her male friends begin commenting on a 'girl' at the bar, Mayim explains the belittling effect the word has on its subject.
"Language matters, words have meaning, and the way we use words changes the way we see things in our mind," she explains.
"So when we use words to describe adult women that are typically used to describe children, it changes the way we view women, even unconsciously...it implies that they're inferior to men, even if that's not what most people intend."
As Mayim quite rightly asserts, you wouldn't walk into a bank, see a grown man working there, and refer to him as a boy. Nor are you likely to do the same in a bar situation.
Indeed, as the actress puts it, we are far less likely to refer to men as boys, because it's "demeaning and emasculating."
Mayim points out that there are women who don't mind being seen as diminutive, and that's fine, but she has a message for them.
"The terms we have for women are outdated and insensitive, and they assume a structure of power where women are on top and women are on the bottom.
"We know better now, it's up to us to change this narrative."
And to those who call women girls? "I know your intentions are probably good, but I hope you can learn to see the unintended and negative impact your words can have.
"Girls tend to be under the age of 18 and live with their parents," she tells them.