Mishka nudged me painfully in the side with his sharp elbow.
Руки у него были по локоть вымазаны в краске.
His arms were smeared with paint up to the elbows.
This entry is concerned with the word локоть denoting a part of the human arm. It is also used to refer to the part of the clothing that covers the elbow, e.g. Локти на пиджаке протёрлись "The elbows of the jacket were worn through,"
a meaning not described in this dictionary.