Friend. Urdu from Persian. wide range of meaning and usage from 'someone whom you have just met' to 'beloved'. Commonly heard 'arre yar' which is a term either of contradiction like 'come off it' or of surprise like 'fuck me'.
Area of specific interest. Heard recently on BBC Radio 5, ‘Right up your Strasse’. Clearly calqued from ‘right up your street’ but with a tone of contempt. Does the rhyme and association with ‘up your arse’ have anything to do with it?