"Earthy" can mean a few things. Isn't English confusing??
Basically, it could taste literally like dirt like potatoes. It can have a mild and musky flavor. Turnips are 'earthy' to me. And mushrooms. I guess something that tastes well-rounded and natural.
I hope that helps.
An earthy flavor is plain, un-decorated, simple. It also seems like it has come from the earth. For example, some eggs and some potatoes.
Well, it means just that you taste earth... It is possible with a lot of vegetables, or with wines for example. Mushrooms are also a good example of earthy flavour.
I looked it up on an online dictionary and it said, "rough, coarse, or plain in taste."
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