somebody who rides; specif somebody who rides a horse, a bicycle, or a motorcycle
something added by way of qualification or amendment, e.g. a clause appended to a legal document
something added by way of qualification or amendment, e.g.:
a clause appended to a legal document, esp a legislative bill at its third reading in the British Parliament
a statement, e.g. a recommendation for mercy, appended to a jury's verdict
a part of something that overlies, moves along, or reinforces another
riderless adj