late 13c., "thing that rolls, roller for moving heavy objects;" late 14c., "a rolling pin," agent noun from roll (v.). The sense of "heavy cylinder for smoothing the ground is from 1520s.
Meaning "hair-curler" is attested from 1795; as a printer's tool, by 1790; as a device for applying paint, etc. to a flat surface, by 1955. The meaning "long, heavy, swelling wave" is by 1829. In combinations, it often means "done on or by means of roller-skates," for example roller derby (by 1936; see derby); roller hockey (1926); roller-disco (1978). Disparaging religious term holy roller is attested from 1842, American English, from the alleged rolling in the church aisles done by those in the Spirit.
Old English blæd "a leaf," also "a leaf-like part" (of a spade, oar, etc.), from Proto-Germanic *bladaz (source also of Old Frisian bled "leaf," German Blatt, Old Saxon, Danish, Dutch blad, Old Norse blað), from PIE *bhle-to-, suffixed form (past participle) of root *bhel- (3) "to thrive, bloom."
Extended in Middle English to the broad, flattened bone of the shoulder (c. 1300) and the cutting part of knives and swords (early 14c.). The modern use in reference to grass may be a Middle English revival, by influence of Old French bled "corn, wheat" (11c.), which is perhaps from Germanic. The cognate in German, Blatt, is the general word for "leaf;" Laub is used collectively as "foliage." Old Norse blað was used of herbs and plants, lauf in reference to trees. This might have been the original distinction in Old English, too. Compare leaf (n.). Of men from 1590s; in later use often a reference to 18c. gallants and dashing rakes, but the original exact sense, and thus signification, is uncertain.
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Definitions of Rollerblade
travel on shoes with a single line of rubber wheels attached to their soles;