the unauthorized interference in a legal action by a person having no interest in it (as by helping one party with money or otherwise to continue the action) so as to obstruct justice or promote unnecessary litigation or unsettle the peace of the community; "unlike champerty, criminal maintenance does not necessarily involve personal profit"
moving from one place to another and back again; "he traveled back and forth between Los Angeles and New York"; "the treetops whipped to and fro in a frightening manner"; "the old man just sat on the porch and rocked back and forth all day"