1
a
: 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
cemented; cementing; cements
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
cementer
noun
Cite this Entry
“Cement.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cement. Accessed 27 Oct. 2026.
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