Cromwell \c-romwe-ll, cr(om)-well\ as a boy's name is of Old English origin, and the meaning of Cromwell is "winding stream". Place name. 17th-century reformer Oliver Cromwell, actor James Cromwell. Baby names that sound like Cromwell are Carmelo, Carmello, Carmeli and Carmel. Other similar baby names are Bromwell and Crowell.