Type: object
Object Properties
I regret calling this a "large icon". It's more like a medium-sized image with a picture of the vendor's mug on it, trying their best to look cool. Not what one would call an icon.
Type: string
Type: string
If we replaced the icon with something more glitzy, this is the original icon that the vendor had according to the game's content. It may be more lame and/or have less razzle-dazzle. But who am I to tell you which icon to use.
Type: string
Vendors, in addition to expected display property data, may also show some "common requirements" as statically defined definition data. This might be when a vendor accepts a single type of currency, or when the currency is unique to the vendor and the designers wanted to show that currency when you interact with the vendor.
Type: array
This is the icon used in parts of the game UI such as the vendor's waypoint.
Type: string
This is the icon used in the map overview, when the vendor is located on the map.
Type: string
This is apparently the "Watermark". I am not certain offhand where this is actually used in the Game UI, but some people may find it useful.
Type: string
Type: string
Type: string
Note that "icon" is sometimes misleading, and should be interpreted in the context of the entity. For instance, in Destiny 1 the DestinyRecordBookDefinition's icon was a big picture of a book.

But usually, it will be a small square image that you can use as... well, an icon.

They are currently represented as 96px x 96px images.
Type: string
If this item has a high-res icon (at least for now, many things won't), then the path to that icon will be here.
Type: string
Type: boolean