The noun 炸药 (zhàyào) means "explosives" or "dynamite." It refers to substances capable of causing an explosion. For example, 仍含有炸药 means "still contains explosives."
警方在仓库里发现了大量炸药。
jǐngfāng zài cāngkù lǐ fāxiàn le dàliàng zhàyào.
The police found a large amount of explosives in the warehouse.
施工队用炸药炸开了那座山。
shīgōngduì yòng zhàyào zhà kāi le nà zuò shān.
The construction crew used explosives to blast open the mountain.
运输炸药需要特别的许可证。
yùnshū zhàyào xūyào tèbié de xǔkězhèng.
Transporting explosives requires a special permit.