• 一隻いっせき — one ship (counter)
• 隻眼せきがん — one eye; monocular vision
• 隻語せきご — a brief remark; only a few words
• 隻数せきすう — the number of ships (counted in 隻)

隻 combines the bird radical 隹（ふるとり） with a hand-like element on the left. The image is of catching or holding a single bird — “one out of the pair.” From there it came to mean one side of something paired, and later became a counter for large things like ships.