cement

American  

[si-ment] / sɪˈmɛnt /

noun

1. any of various calcined mixtures of clay and limestone, usually mixed with water and sand, gravel, etc., to form concrete, that are used as a building material.

2. any of various soft, sticky substances that dry hard or stonelike, used especially for mending broken objects or for making things adhere.

3. Petrography. the compact groundmass surrounding and binding together the fragments of clastic rocks.

4. anything that binds or unites.

   Time is the cement of friendship.

5. Dentistry.

   1. a hardening, adhesive, plastic substance, used in the repair of teeth for anchoring fillings or inlays, for filling, or for fastening crowns.

   2. Informal. cementum.

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verb (used with object)

1. to unite by or as if by cement.

   to cement stones to form a wall; to cement a relationship.

   Synonyms:

   secure, fuse, bind, join, merge

2. to coat or cover with cement.

   to cement a floor.

verb (used without object)

1. to become cemented; join together or unite; cohere.

cement British  

/ sɪˈmɛnt /

noun

1. a fine grey powder made of a mixture of calcined limestone and clay, used with water and sand to make mortar, or with water, sand, and aggregate, to make concrete

2. a binder, glue, or adhesive

3. something that unites or joins; bond

4. dentistry any of various materials used in filling teeth

5. mineral matter, such as silica and calcite, that binds together particles of rock, bones, etc, to form a solid mass of sedimentary rock

6. another word for cementum

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verb

1. to reinforce or consolidate

   once a friendship is cemented it will last for life

2. to join, bind, or glue together with or as if with cement

3. to coat or cover with cement

Other Word Forms

• cementable adjective
• cementer noun
• cementless adjective
• recement verb
• well-cemented adjective

Etymology

Origin of cement

1250–1300; < Latin cēmentum, variant of caementum (singular of caementa unprocessed cuttings from the quarry, i.e., rough stone and chips) < *caed-mentom, equivalent to caed ( ere ) to cut + -mentum -ment; replacing Middle English cyment < Old French ciment < Latin, as above

Explanation

Cement is a material that's used to build very strong, hard surfaces and structures. Cement is an ingredient in both mortar, which holds bricks together, and concrete, with which dams and roads and buildings are constructed. Cement begins as a powder made of clay and limestone, and after it's mixed with water and, often, sand, it's used to strengthen and bind things — as the mixture dries, it becomes hard and solid. A version of cement has been around since the third century BCE, in Mesopotamia. The word comes from the Latin root cæmenta, "stone chips for making mortar," from caedere, "to cut or chop."

Example Sentences

When you think of galleries, you don’t think of cement or gray walls, but it’s a nice addition.

From Los Angeles Times • Apr. 21, 2026

The acquisition could help to cement Eli Lilly’s position in the $240 billion global cancer-drug market.

From Barron's • Apr. 20, 2026

China is moving quickly to dominate the humanoid-robotics industry and cement its place in the global supply chain.

From The Wall Street Journal • Apr. 20, 2026

But that sand itself is also in high demand for cement, for construction, for building shoulders for highways, for filling in wetlands for development.

From Slate • Apr. 20, 2026

Dad sat with his right leg sticking out into the aisle, a hard cast wrapped around his foot like a cement boot.

From "The Line Tender" by Kate Allen

Related Words

• adhesive
• mud
• plaster
• sand