Face with crossed-out eyes emoji 😵 is part of the Smileys & Emotion and Unwell emojis. On some systems it can be accessed by using :face_with_crossed_out_eyes:, :dizzy_face: or :knocked_out: shortcodes.
It was approved as part of Unicode in 2010 so it should be displayed properly on all devices.
Tags: Crossed-out eyes, Dead, Face and Knocked out