Semantic systems vary substantially across languages, but may nonetheless be constrained by structure in the world. Malt et al. (2008) advanced such an argument in the domain of locomotion. In their study, speakers of English, Spanish, Japanese, and Belgian Dutch named video clips of an individual locomoting on a treadmill. In all four languages, naming respected the distinction between walking and running gaits, suggesting a universal semantic constraint based on a biomechanical discontinuity.