An animal that has a bobtail, such as certain canines or nags.
(agriculture) A tractor which performs without its trailer.
A tractor-trailer that is relatively short in length.
(poker, often attributive) An open-ended straight or four flush.
a bobtail flush
A bobtail squid.
A bobtail skink.
verb
(agriculture) To drive a tractor without its trailer.
2002. David Diamond. The Trucker & The Professor, Wired (magazine), Issue 9.12http://www.wired.com/wired/archive/9.12/sheffi.html?pg=2&topic=&topic_set=
He deposits his trailer at a Marten facility in nearby Stockton, and then drives without the trailer - that's called "bobtailing".
To drive a truck or other vehicle without its trailer.
2003. Bergmann Co. Bergmann's Cleaning History:https://web.archive.org/web/20071012131035/http://bergmanns.com/company_history.asp
W.C. Bergmann was supplementing his meager lamplighter's income by "bobtailing"… picking up laundry and cleaning in his horse drawn truck...