Laravel 5 Route Strange Behaviour

I have a Laravel site set up on a Homestead box, so I'm accessing it on sitename.app:8000. I have a route called "news" but when I try to go to sitename.app:8000/news I get oddly bounced out to sitename.app/news/.

If I change the routename to "news2" I can access the desired controller action as per normal at sitename.app:8000/news2. So somehow it's "news" itself that has become uncooperative - and I'm pretty sure that we aren't even getting as far as the NewsController, when I try to access that url.

Can anyone work out from these symptoms what might be going wrong? One "news"-related change I made at some point was to add $router->model('news', "App\News"); in the boot method of the RouteServiceProvider, but removing this doesn't seem to make the difference.

ETA: People keep asking for the routes.php file. I can literally remove everything from the file except

Route::get('news', function() {
    return "hello world";
});

Route::get('news2', function() {
    return "hello world";
});

and /news2 will work but /news will bounce me out. So I remain pretty convinced that the problem is somewhere deeper than routes.php...