plural nebulae /-ˌliː/ /ˈnɛbjəˌliː/ also nebulas plural nebulae /-ˌliː/ /ˈnɛbjəˌliː/ also nebulas Learner's definition of NEBULA
[count] astronomy
1
: a cloud of gas or dust in space that can sometimes be seen at night星云状气体(或积尘)
2
: a group of stars that are very far away and look like a bright cloud at night星云
— nebular
/ˈnɛbjəlɚ/ adjective