At dinner last night (Sunday 12/13/2015), I was asked if I knew of a word for being happy (or perhaps waking up happy) because of a good dream. I didn't. Do you?

Searched the archives here for both
happy sleep
happy dream
and didn't see anything that seemed to be along those lines.

I have periods of dreaming when I wake up and although I can't remember all the details of the dream I dislike the dreams I was having. I think, "What a waste of time. I didn't like that at all." So in answer to your question I would say 'grateful'. Mike.
Mottainai is a Japanese term conveying "what a waste."

I am a big fan of pho. I'm always on the lookout for a good bone broth, which is where I learned the word today.

I had a dream last night that I've had before. It was a little different this time. Looking for a house, three kittens were with me this time...they were ludic. A word I learned just this morning after my dream.

I don't know a word for happy dreaming but, I never considered it a waste before.
on a somewhat related note:

the worthless word for the day was: paleomnesia

[fr. Gk paleo-, ancient + -mnesia, condition of
memory] a good memory of events of the distant past

an interesting word, but it doesn't seem to have
ever been used for much of anything..

"Not all of Mrs. Byrne's offerings are addlepating
esoteria; some are refreshingly useful, like
paleomnesia, "happy memories from events far in
the past," and euneirophenia, "peace of mind after
a pleasant dream."
- Christi M. Smith, Verbibore's Feast
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