To travel as a stowaway aboard a freight train on a railroad.

(colloquial) To alight.

(within the EC) The circumvention of a trade quota by registering a business (or a fishing vessel) in a foreign country in order to benefit from its quota

(pharmacology) lead hopping

(pharmacology) the identification of isofunctional molecular structures with significantly different molecular backbones

plural of bunny hop

to have numerous jobs in a short period of time

(intransitive) To travel from island to island in a certain area, especially as a tourist to visit numerous islands.

Alternative spelling of barhop

(informal) In a situation for which one is unprepared. / (informal) In a situation of change, especially from a known to an unknown state.