What kind of name is Lousewort?

A side-effect of trying the natural dyeing is that I'm suddenly aware of how few plants and flowers I recognise - of course I do recognise them (well, some of them), I just can't name them which isn't that helpful when I'm looking at lists of plants that will produce some colour.

I'm okay at this sort of thing..

.. (that's my lawn by the way, *blush*) but anything less blindingly obvious than that and I'm stumped.

So I bought a little field guide to wildflowers and started flicking through it. And in passing discovered that the tiny flowers I knew in my childhood as honey flowers (or honey flooers) are more generally known as Lousewort. Lousewort? What kind of horrible name is that for such teeny, pretty purveyors of sweetness?