The Collaborative International Dictionary of English v.0.48:
Rambler \Ram"bler\ (r[a^]m"bl[~e]r), n. One who rambles; a rover; a wanderer. [1913 Webster]WordNet (r) 3.0 (2006):
rambler n 1: a person who takes long walks in the country 2: a person whose speech or writing is not well organized