"path for pedestrians on the side of a street," 1721, from side (adj.) + walk (n.). The use of sidewalk for pavement has been noted in England as an Americanism at least since 1902.
Entries linking to sidewalk
side adj.
late Old English, "long, broad, spacious; extending lengthwise," from side (n.). Compare Old Norse siðr "long, hanging down." From late 14c. as "being from or toward the side," hence also "subordinate." Also "apart from the main course" of anything, as in side-road (1854); side-trip (1911). In side-eye (by 1922) the notion is "directed sideways."
walk n.
c. 1200, "a tossing, rolling;" mid-13c., "an act of walking, a going on foot;" late 14c., "a stroll," also "a path, a walkway;" from walk (v.). The meaning "broad path in a garden" is from 1530s. Meaning "particular manner of walking" is from 1650s. Meaning "manner of action, way of living" is from 1580s; hence walk of life (1733). Meaning "range or sphere of activity" is from 1759. Sports sense of "base on balls" is recorded from 1905; to win in a walk (1854) is from horse racing (see walk-over). As a type of sponsored group trek as a fund-raising event, by 1971 (walk-a-thon is from 1963).
pavement n.
mid-13c., "paved or tiled surface of ground," from Old French pavement "roadway, pathway; paving stone" (12c.) and directly from Latin pavimentum "hard floor, level surface beaten firm," from pavire "to beat, ram, tread down," from PIE root *pau- (2) "to cut, strike, stamp." From c. 1300 as "a paved roadway," gradually passing in modern times to the sense of "a sidewalk, paved footway on each side of a street." By 1878 as "material of which a pavement is made."