Telepathic Communication

While the vast majority of life in Altwaus relies on verbal communication, there are some who are able to communicate wordlessly through the direct mental linking of minds. Referred to generically as "telepathy" the exact means that this communication occurs varies by species and origin. 
Spellcasters, such as the arcanist magi of the The Collegiate Arcane can communicate non-verbally (with assistance) even over great distances - however this is rare enough that is not a common ability among the majority of arcanists. Other sorcery is able to communicate wordlessly in some instances, as demonstrated by primalists and even divine-blessed warlocks are able to touch minds at times - albeit normally under only very specific circumstances. 
In the case of these spellcasters, the minds are linked (through great difficulty) by sorcerous energies that gather, focused, and then sustained through the practice of spellcraft. In contrast to this, some species are capable of innate telepathic communication - often supplementing this ability with traditional verbal communication through the common tongue. Some species, such as the muzancab hives use telepathic communication within the species hive to create a "hive mind" that is able to respond to stimulus and commands at the speed of thought. 
Lastly, there is a poorly understood form of mental communication that is believed to exist - even in species such as humans that are not known to demonstrate psychic or telepathic abilities outside of sorcerous magic. This Psychic Magic is similar to sorcery in that the telepathic communication demonstrate it a result of controlled magical energy, except that the ability is believed to be innately developed within certain individuals of a species - as opposed to a biological imperative for the species.