Wiktionary
quinolizidine
n. (context organic compound English) A bicyclic saturated heterocyclic compound in which a nitrogen atom serves as a bridge.
Wikipedia
Quinolizidine
Quinolizidine (norlupinane, octahydro-2H-quinolizine) is a nitrogen-containing heterocyclic compound. Some alkaloids (e.g. cytisine and sparteine) are derivatives of quinolizidine.