According to the National Library of Medicine:
Persistent postural-perceptual dizziness (PPPD)...is a chronic vestibular disorder that manifests with waxing and waning symptoms of dizziness, unsteadiness, or nonspinning vertigo that last for 3 months or more and are exacerbated by upright posture, active or passive motion of self, and exposure to environments with complex or moving visual stimuli.