Quasqueton said:
For instance, should a DM say, “an ornate jewelry box”, or “a teakwood jewelry box carved with elaborate designs of butterfly-winged fairies on roses, tulips, and daffodils”?
The second one.
Should a DM describe a magic sword as, “a glowing sword with a gem,” or “a heavy, bright-steel sword of exquisite workmanship, etched with extensive interweaving designs; a marquee-cut emerald at the base of the blade is the source of a soft green glow”?
Option #2.
Should a DM describe the castle on the hill as, “a castle on the hill,” or “a gray fortress, with tall towers topped by bright pennants, and surrounded by crenellated walls of made of large granite stones”?
The latter.
How much detail should a DM give to guide the Players’ imaginings of the world they experience? Is using “ten-dollar words” a sign of a good DM, or should the DM keep description to more natural, conversational terms?
All of the the above are not "flowery". At least not as I see it. The examples you've given are short, useful, and VASTLY more interesting and memorable for being 20 words instead of just 2. They are not endless, tedious, and intrusively descriptive where you get a PARAGRAPH of detail for a throwaway item, a simple "establishing shot" of a one-time location, or devoting time and effort to describing things
ad nauseum.
Flowery description is putting on your Shakespeare fake beard and hat and describing a flower with a sonnet in iambic pentameter. But saying "castle on the hill" is NON-descriptive. It doesn't tell you a bloody thing. It sparks nobodys imagination, it practically entails an implied description of something boring, tedious, and present only by absolute necessity. If you go through your entire campaign this way you can easily imply this about your entire campaign world. On the other hand, using a description like, "a gray fortress, with tall towers topped by bright pennants, and surrounded by crenellated walls of made of large granite stones," gives players all the description they need, goes WAY beyond giving them NOTHING to work with, and even if they never return there they will be able to immediately associate the name of the place with that ONE LINE description that you gave it. Your entire game world comes to life with brief descriptions like these and it takes almost no effort - unlike a genuinely
flowery description which is rarely what is needed or desired.
All that said you want to exercise some discretion in what you describe, when, and why. Sometimes a locked chest is
just another chest. You don't need to
describe it, just state what it is. But sometimes you WANT players to take an interest in one NPC over another, or to reinforce some seemingly minor detail of your game world. You therefore sometimes need to give a line or two of description to things that really DON'T need it, just to act as a reminder that the PC's are not sitting at your kitchen table like you are. It may be just an ornate jewelry box, but if you describe it as “a teakwood jewelry box carved with elaborate designs of butterfly-winged fairies on roses, tulips, and daffodils” you open up great vistas of possibility and you-are-there qualities. You'll find that players will actually keep for their PC the box with the one line of description rather than the mere "ornate jewelry box" that has twice the gold piece value simply because the box with the description LIVES in the imagination. The box with just the GPV is just that - a gold piece value item like any other and it's form is irrelevant. By giving it no more description than what it is you imply that it HAS no more relevance. It is by occasionally describing even mundane items, characters, and places that a campaign is given a genuine aura of actually existing somewhere - even if it IS just in the imagination.