Icelandic has a special group of verbs that end in -st. This is known as the "middle voice." Adding -st to a standard base verb changes its relationship to the subject, usually making the action reciprocal, mediopassive, or describing a state of mind.
Reciprocal actions (Doing something to each other)
The most common use of -st verbs is to show that two or more people are performing an action on one another. For example, faðma means "to hug," but faðmast means "to hug each other."
Other common reciprocal verbs include hittast (to meet each other), kyssast (to kiss each other), and sjást (to see each other). Notice how the base meaning shifts to a mutual action.
Reflexive and passive actions (Getting or becoming)
Sometimes, the -st ending indicates that an action is happening to the subject, rather than the subject doing it to someone else. It can act like a passive voice or describe something happening spontaneously.
For example, meiða means "to hurt" (an active action against someone), but meiðast means "to get hurt."
It also applies to inanimate objects doing things "by themselves," like a door opening without anyone pushing it.
Mental states and emotions
Finally, some -st verbs express an internal feeling or a state of mind. For example, hræða means "to scare" (inflicting fear on someone), but hræðast means "to fear" or "to be afraid" (experiencing the emotion yourself).
Once you know these patterns, you can often guess the meaning of an -st verb just by looking at its base form!
