What are the different types of trademark similarity?

Trademark similarity for word marks and figurative marks are 1) aural,: how it sounds, 2) visual; how it looks, and b) conceptual.; the concept it conveys. So Mycrowsoft who be considered too aurally similar to Microsoft. Visual similarity would prevent the registration of airdmd as too visually similar to airbnb (as well probably as aurally). Two trademarks are conceptually similar if they convey the same are conceptually similar if they convey the same concept or idea. So Lemon luggage and Lime baggage are concepually similar.