This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
艏 combines 舟 (boat) with 首 (head). It likely originally referred to the bow or front part of a boat, but the exact historical development is uncertain.
The kanji has 舟 (boat) on the left and 首 (head) on the right. Picture the head of a boat, the bow, but remember that its standalone meaning is unclear.
For シュウ, imagine the bow of a boat cutting through the water with a sharp 'shoo' sound: shoo -> シュウ.