To sleep, lie at ease, lounge, relax.
This is a pleasant word for just relaxing. Contrary to popular belief Hawaiians were hard workers (and I like to think that many Hawaiians today are also hard workers). They woke up at the crack of dawn so they could get the majority of hard work done before the sun was up high. I remember my grandfather getting up super early to begin his day by raking the entire yard and pull weeds. I just love driving through homestead areas in the morning because you inevitably see this tradition continuing. Someone is outside raking up the leaves, scooping them into the cut pakini scooper. And it isnt just kupuna. I see makua (parents) outside doing it and even keiki on some early weekend mornings.
This word sometimes replaces moe (for sleep) in poetry because moe can also suggest death.
Ua kau ke keha i ka uluna, ua hi'olani i ka moena - the head rests on the pillow, stretching out on the mat [relax after work is done] This line comes from a chant called Ke Welina, dedicated to Käne.