If you mean to the names of the HTML element - the most common ones are 'checkout', 'goto_pp' and 'goto_gc'.
Professional Shopify Partner. Check out our Apps in the Shopify App Store:
? Super Gift Wraps | ✅ Terms and Conditions Checkbox | ♬ Custom Background Music
⏳ Scarcity: Cart Countdown Timer | ? SocialBar - Social Media Icons | ⟳ Idler - Auto Store Refresher
✨ Magical Browser Tab Animations | ⚠️ Product Warnings & Pop Ups | ⏰ Low In Stock Alert
❤️ Custom Falling Images Effect | ☔ 3D Falling Snow/Rain Effects | ☝ Colorful Back To Top Button
?♂️ Waze & Google Maps Navigation | ♻ Update Cart Button Remover
Most of the theme developers use the name "checkout."
This would be a perfect candidate for one of the Community App Developer Code Guidelines as described in https://community.shopify.com/c/Custom-Storefronts-Support/Community-App-Developer-Code-Guidelines/t....
We could specify that it is recommended to name the checkout button as "checkout."