A searchable guide to the complete WordPress Icon Library (@wordpress/icons) package from Gutenberg.
import { Icon, thumbsDown } from '@wordpress/icons';
<Icon icon={thumbsDown} />
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" aria-hidden="true" focusable="false"><path d="M19.8 4h-1.5l1 8h1.5l-1-8ZM17 5.8c-.1-1-1-1.8-2-1.8H6.8c-.9 0-1.7.6-1.9 1.4l-1.8 6C2.7 12.7 3.7 14 5 14h4.4l-.8 3.6c-.3 1.3.7 2.4 1.9 2.4h.2c.6 0 1.2-.3 1.6-.8l5-6.6c.3-.4.5-.9.4-1.5L17 5.7Zm-.9 5.9-5 6.6c0 .1-.2.2-.4.2h-.2c-.3 0-.6-.3-.5-.6l.8-3.6c.1-.4 0-.9-.3-1.3s-.7-.6-1.2-.6H4.9c-.3 0-.6-.3-.5-.6l1.8-6c0-.2.3-.4.5-.4h8.2c.3 0 .5.2.5.4l.7 5.4v.4Z"></path></svg>
thumbsDown – WordPress Icon Library