Re: Hasbro has history against it.
Did anyone REALLY think that Apple is only allowed to be used by Apple Computers?
Of course there's precedent. Go search on Companies House for UK companies with Apple in the name. There's hundreds. Hell, there are six "Apple Accountancy" in various forms.
And that's the COMPANY NAME, not just a single tag on a single product. So long as you're not trying to "pass off" as the other company then it's fine. If they have a trademark, they have to pay to register it in EVERY CATEGORY they want to use it in (so trademarks can get very expensive very quickly) and if they don't use it properly in one of those categories, they can lose it.
And even when there is a direct conflict between an established trademark and some "use" of it somewhere, it's not necessarily the trademark that will win: Too generic, only part of the name, other uses predate the trademark, etc.
No company in the world owns the right to a particular, well-known, English word. They can hold certain very limited rights in certain very limited circumstances at their own expense and risk, but that's about it.
Stop using generic worlds to describe your company / product. Google even did it (from "googol"). Windows. Apple. Kindle. Amazon.
But did Zoopla? I doubt it. So you INSTANTLY stand a lot more legal chance in defending a trademark of Zoopla against such things, than of any of the largest IT companies / products out there, even someone is OBVIOUSLY trying to pass itself off as that particular company/product.
Make up some junk. Easy to remember. If you're successful, everyone will learn it. If you're not, nobody will care about your name. And you can *honestly* steer clear of having to deliberately initiate such silly lawsuits because you have to "defend" your trademark.