manhole cover

English Thesaurus

1. a flush iron cover for a manhole (as in a street) (noun.artifact)

hypernym	:	cover, top,
definition	:	covering for a hole (especially a hole in the top of a container) (noun.artifact)

part meronym	:	manhole,
definition	:	a hole (usually with a flush cover) through which a person can gain access to an underground structure (noun.artifact)