侍ふ

さぶらう, さむらうsaburau

Yodan verb with 'hu/fu' ending (archaic) · intransitive · auxiliary

1. to attend (a person of high rank)
2. to wait upon (e.g. a noble)
3. to serve
4. to be
5. to exist
6. to go
7. to come
8. expresses politeness towards the listener

Study it in Yanamino