A path for bicyclists located next to (alongside) a roadway(noun)
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Use "sidepath" in a sentence
"He says mostly whatever comes to mind some of which is entirely sensible then he takes a sidepath in some other direction if the whim hits him."
"Martin Cunningham emerged from a sidepath, talking gravely."
"A thick fog hung over the forest, so that they had to guess their way; but Claudet knew every turn and every sidepath, and thus he and his companion arrived by the most direct line at the rendezvous."