1. against: in anticipation of the time when.

2. crush'd and o'er-worn: crumpled and worn bare.

3. drain'd his blood: i.e., turned a ruddy complexion to pale white.

5. steepy: i.e., steep or precipitous, and therefore dangerous. —Shakespeare seems to imagine the journey into old age as being like a walk along a cliff, from which you could fall into death at any moment.

8. treasure of his spring: his youth.

9. For such a time: i.e., in preparation for that time.  fortify: prepare defenses.

10. confounding: destroying.

11. That he: i.e., so that Time.

12. though: though he will cut.

13. black lines: written words.

14. still green: still young.