other
since
A1
'seit' is a temporal preposition or subordinating conjunction meaning 'since' (time or 'for' in English). As a preposition it governs the dative (seit einem Jahr). As a conjunction it introduces clauses (seit er hier ist). Often expresses an action/state continuing from a past point to the present.
Examples
Ich wohne hier seit 2015.
I've been living here since 2015.
Seit dem Brand vor zwei Jahren war die Halle gesperrt, sodass keine Veranstaltungen mehr stattfanden.
Since the fire two years ago, the hall had been closed, so no events took place anymore.
Details
Mnemonics
Visualize a timeline with a marker labeled 'seit 2010' meaning 'since 2010'.
Seit sounds like 'sight' but means 'since' — link to time.
Notes
'seit' is usually a preposition or conjunction meaning 'since' (indicating starting point in time). In the input the part-of-speech was empty; treat as general temporal connector.