Am I correct that midday is a noun (we commonly gather at midday for lunch) and mid-day is an adjective (we commonly gather here for a mid-day meal)? Or are either acceptable as either noun or adjective? Or is one preferable in either case? Help!
Rwash, welcome to the Grammar Exchange, and thank you for your question.
Personally, I would tend to use "midday" (without a hyphen) both as an adjective and a noun, if I were to use it at all.
The fact is that the word is rather archaic. I would be more inclined to say (or write) "noon" instead.
However, back when the word was in common usage, spelling wasn't standardized. The famous English playwright and poet William Shakspir was known to spell his own name at least sixteen different ways in his lifetime. I'm sure that the hyphenated spelling "mid-day" was perfectly acceptable both as a noun and as an adjective to most people back then. Or, at least, to most people that could read. There really weren't many literati then.
There is a reason I can't simply say noon. It's because I'm discussing a midday program that runs from 11-1.