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
verbcemented; 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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Time Traveler for cement
The first known use of cement was in the 14th century
See more words from the same century