1. to, toward: directional case marker, in a physical sense

2. into, direction of a change: directional case marker in a metaphorical sense; expresses transformation or direction towards a certain time

3. using, out of; with: instrumental case marker, marking material, instruments, or means of doing something

4. due to; from: instrumental case marker, marking causation

5. as; as being; in the state of: instrumental case marker, marking state, manner, status, or capacity

6. as of: instrumental case marker, marking an update in a list of previous events

7. from; egressive case marker, in a physical or chronological sense (archaic)

8. Marks the direct object for certain action verbs, especially verbs that have a direct impact on the object. (Gyeongsang)

9. Used in various expressions

a. See -으로 하여 (-euro hayeo, “because of; via”).

b. See -으로 하여금 (-euro hayeogeum, expresses the agent in a causative construction).

c. See -으로 더불어 (-euro deobureo, “together with”).