• 何枚なんまい — how many sheets
• 枚数まいすう — number of sheets
• 枚挙まいきょ — enumeration
• 一枚目いちまいめ — first sheet/page
• 数枚すうまい — several sheets

枚 combines 木 (tree) with 攴 (to strike), evoking thin wooden boards or planks. By extension, it became the default counter for flat, thin items like paper, plates, and tickets.