another.” 18 Oxford English Dictionary 424 (2d ed. 1989) (OED). Accord, N. Webster, An American Dictionary of the English Language 1406 (C. Goodrich & N. Porter eds. 1873) (“[t]he act of transporting, carrying, or conveying from one place to another”). And we must apply this definition in a “practical,” not a “theoretical,” way. Stewart, supra, at 496. Consequently, in our view a structure does not fall within the scope of this statutory phrase unless a reasonable observer, looking to the home’s physical characteristics and activities, would consider it designed to a practical degree for carrying people or things over water.
B
Though our criterion is general, the facts of this case illustrate more specifically what we have in mind. But for the fact that it floats, nothing about Lozman’s home suggests that it was designed to any practical degree to transport persons or things over water. It had no rudder or other steering mechanism. 649 F.3d, at 1269. Its hull was unraked, ibid., and it had a rectangular bottom 10 inches below the water. Brief for Petitioner 27; App. 37. It had no special capacity to generate or store electricity but could obtain that utility only through ongoing connections with the land. Id., at 40. Its small rooms looked like ordinary nonmaritime living quarters. And those inside those rooms looked out upon the world, not through watertight portholes, but through French doors or ordinary windows. Id., at 44–66.
Although lack of self-propulsion is not dispositive, e.g., The Robert W. Parsons, 191 U.S. 17, 31 (1903), it may be a relevant physical characteristic. And Lozman’s home differs significantly from an ordinary houseboat in that it has no ability to propel itself. Cf. 33 CFR §173.3 (2012) (“Houseboat means a motorized vessel ... designed primarily for multi-purpose accommodation spaces with low
