since

(adverb, conjunction, preposition)

adverb

1. From a specified time in the past.

- I had seen him previously, but hadn't seen him since.

conjunction

1. From the time that.

- I have loved you since I first met you.

2. Because.

3. (obsolete) When or that.

preposition

1. From (time).

- I have known her since last year.