Per VognsenCame across English 'lee' (meaning shelter from the elements) in a book I'm reading and thought it had to be a cognate of Danish 'læ' and 'ly'. From a quick search I can't find any other modern language with the 'ly' vs 'læ' distinction but I'm probably missing some.
Ordnet says ly is from Old Norse hlý (warmth) and læ is from Old Norse hlé so maybe ly and læ are not actually related but that's a weird coincidence in sound considering their close meanings in Danish.
Found some old newsgroup posts with people opining on ly and læ. The responses match my intuitions but my ear for Danish has deteriorated from under-use: https://dk.kultur.sprog.narkive.com/W66jvPh1/ly-og-lae.
It's funny to put any of this through a translator since both ly and læ turn into 'shelter' so everything just reads like a bad comedy routine: "When do you use 'shelter' and when do you use 'shelter'?"
Thomas Fach-Pedersen@pervognsen In my mind, a “læ” is something that provides “ly”. I think. Like a shelter provides shelter. It’s not words I use a lot 🙂
Owen Anderson@pervognsen I don’t know if it helps, but in nautical terminology leeward is pronounced “loo-ward”. Maybe preserving an older form?