gateway drug

US /ˈɡeɪtweɪ drʌɡ/
UK /ˈɡeɪtweɪ drʌɡ/
"gateway drug" picture
1.

入門毒品, 引路毒品

a drug whose use is thought to lead to the use of more dangerous drugs (such as heroin or cocaine)

:
Marijuana is often considered a gateway drug by some.
大麻常被一些人認為是入門毒品
The theory of gateway drugs suggests a progression from less harmful to more harmful substances.
入門毒品理論認為,毒品使用會從危害較小的物質發展到危害更大的物質。