Dreamy Gloria hasn't a map, unfortunately (15)

I believe the answer is:

phantasmagorial

I'm a little stuck... Click here to teach me more about this clue!

'dreamy' is the definition.
Both the definition and answer are adjectives.
Perhaps you can see a link between them that I don't see?

'gloria hasn't a map unfortunately' is the wordplay.
'unfortunately' indicates anagramming the letters (a bad or unfortunate spelling).
'gloria'+'hasnt'+'a'+'map'='gloriahasntamap'
'gloriahasntamap' with letters rearranged gives 'PHANTASMAGORIAL'.

Can you help me to learn more?

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.