"Skin-popping," or sometimes simply "popping."
Black tar heroin appears black or dark brown under a black light due to its composition, which does not typically fluoresce or emit light under ultraviolet light.
Twisted means messed up; not right; strange
cat is under the table
It's an Opiate, Class A in UK.
Have you noticed this is under "English"
It is about when he stopped heroin and where he shed some blood "under the bridge"
They can be. They are under the influence of a strong narcotic. People react differently to these.
feeling under the weather
Under the weather, laid up.
It is under Literary Devices and Figures of Speech - that is under English Language, which is under Literature and Language.
* Tush or tushy (from the Yiddish language "tuchis" or "tochis" meaning "under" or "beneath")
Vital Information Resources Under Siege (Slang)