since

adverb

1. from then until now: she arrived Tuesday and has been here ever since
2. at some or any time between then and now; subsequently: he was ill last week but has since recovered
3. before the present time; before now; ago: they are long since gone

1. continuously from (the time given) until now: out walking since one o'clock
2. during the period between (the time given) and now; subsequently to: many achievements since his election

conjunction

1. during the period from the specified time or event until the present: I haven't seen him since we were in high school
2. continuously from the time when: I've been lonely since he left
3. inasmuch as; because: since you are finished, let's go