When the concrete was still fresh on the side walk, two of the Ned's friends drew their initials in it to cement their friendship in a concrete manner.
2. A hard, strong construction material consisting of sand, conglomerate gravel, pebbles, broken stone, or slag in a mortar or cement matrix formed by the coalescence of those separate particles or parts into one mass; a solid.
3. A mixture of cement, sand, aggregate, and water in specific proportions which hardens into a strong stony consistency over varying lengths of time.
4. Etymology: "actual, solid" from Latin concretus, "condensed, hardened, thick, hard, stiff, curdled, congealed, clotted"; figuratively "thick; literally, "grown together"; past participle of concrescere, "to grow together"; from com-, "together" + crescere, "to grow".
"Each year billions of tons of concrete become the stuff of buildings, highways, dams, sidewalks, and even artwork. The Romans invented cement-based concrete and used the material to build the Pantheon."
2.Being specific or definite: "So far, the police don't have any concrete evidence that the boy actually broke the window of the neighbor's car."