noun: (electronics) Initialism of through-hole technology. [(electronics) Mounting scheme used for electronic components that involves the use of leads on the components that are inserted into holes drilled in printed circuit boards and soldered to pads on the opposite side.]
noun: (chemistry) Abbreviation of tetrahydrothiophene. [(organic chemistry) A saturated, five-membered heterocycle containing one atom of sulfur; it is added to natural gas to provide it with a detectable smell.]
