(organic chemistry) The highly chlorinated ester trichloromethyl chloroformate that is used in organic synthesis, and was once used as a military poison
headspring
headspring
noun
(gymnastics) A move in which the gymnast places both hands on the mat with the top of the head about 6 inches in front, pushes off with the hands while flipping the legs overhead, and lands on the feet.
A fountainhead; a source.
A spring that sits at the top of a mechanism, pushing the internal parts inward.