All answers start with SI.
-1. SI + Stimpy's friend = Alarm. 5 letters
-2. SI + Not old = Tendon. 5
3. SI + to indicate, or mark = Annotation made in the left or right margin. 8 si--n--e
-4. SI + jewelery worn by rappers, for instance = Brother or sister. 7
-5. SI + substance used to make roads = Indian musical instrument. 5
-6. SI + Happiness, or pleasure = A source of illumination on the side of something. 9
-7. SI + distance equal to approximately 1.6 kilometres = A figure of speech that compares one thing with another. 6
-8. SI + a municipality in Eastern Germany = Threatening or foreboding. 8
-9. SI + Called on a communications device = Drew off, or transferred from one container to another by means of a tube. 8
-10. SI + The period from Ash Wednesday to Holy Saturday = Quiet. 6