When you say “I only wash my hair once a week”, does that mean you only shampoo it once a week, or only get it wet once a week?

MK • 31 - wife - Dog Mom

I’m so confused!! I always see girls talking about how they wash their hair once weekly, but their hair looks clean! And not “I have a pound of dry shampoo in my hair” clean, but actually clean! Does ‘not washing’ your hair mean you can still run it under the water when you shower but not apply shampoo to it? Please explain. I have no sisters nor female cousins so sometimes my beauty knowledge is extremely limited, lol.