(also haironautic, haironautical) Elaborately and clearly artificially sculpted hairstyles that require a degree in engineering to create and maintain, and that in some cases could carry the wearer aloft were it not for the pounds of product required to achieve them. Found most commonly at weddings. As an adjective, used to describe the products and tools required to accomplish these hair arrangements that appear to defy the laws of physics.
Wedding guest 1: "Is it just me, or are the bridesmaids in this wedding sporting some serious haironautics?"
Wedding Guest 2: "For sure, that last gust of wind would have sent the one with the wingy things airborne if she hadn't been weighed down by all that product."