Tic
A tic is a sudden, repetitive, nonrhythmic motor movement or vocalization involving discrete muscle groups. Tics can be invisible to the observer, such as abdominal tensing or toe crunching. Common motor and phonic tics are, respectively, eye blinking and throat clearing.
Sidecar
A sidecar motorcycle is a three-wheeled vehicle with the side wheel not directly aligned with the rear motorcycle wheel, and is usually powered by the rear wheel only. This is different from a motor tricycle (trike), where both rear wheels are powered and share a common axle. However, either P.V. Mokharov of the Soviet Union or H.P. Baughn of Great Britain seem to have been the first to employ a driven sidecar wheel in 1929. Baughn two-wheel-drive outfits were so successful in trials events in the early 1930s that there were attempts to have the ACU ban them from competition. A great many companies experimented with two-wheel drive in sporting events and indeed many companies employed them in military vehicles prior to the commencement of World War II. Currently, the Russian manufacturer Ural produces several models with two-wheel drive that can be engaged as desired.