Definition of cement
(Entry 1 of 2)
1a
: concrete
b
: a powder of alumina, silica, lime, iron oxide, and magnesium oxide burned together in a kiln and finely pulverized and used as an ingredient of mortar and concrete
also
: any mixture used for a similar purpose
2
: a binding element or agency: such as
a
: a substance to make objects adhere to each other
b
: something serving to unite firmly
justice is the cement that holds a political community together— R. M. Hutchins
3
: cementum
4
: a plastic composition made especially of zinc or silica for filling dental cavities
5
: the fine-grained groundmass or glass of a porphyry
cement
verb
cemented; cementing; cements
Definition of cement (Entry 2 of 2)
1
: to unite or make firm by or as if by cement
Pebbles were cemented together by clay. has cemented his role as a leader on the team— T. W. Smith
2
: to overlay with concrete
cemented the cellar floor
: to become cemented
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Merriam-Webster unabridged
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The first known use of cement was in the 14th century
See more words from the same century