Collins English-English Dictionary

pyramid ['pɪrəmɪd]

1. 1. n a huge masonry construction that has a square base and, as in the case of the ancient Egyptian royal tombs, four sloping triangular sides

2. 2. n an object, formation, or structure resembling such a construction

3. 3. n [maths] a solid having a polygonal base and triangular sides that meet in a common vertex

4. 4. n [crystallog] a crystal form in which three planes intersect all three axes of the crystal

5. 5. n [anatomy] any pointed or cone-shaped bodily structure or part

6. 6. n [Finance] a group of enterprises containing a series of holding companies structured so that the top holding company controls the entire group with a relatively small proportion of the total capital invested

7. 7. n [chiefly US] the series of transactions involved in pyramiding securities

8. 8. n [plural] a game similar to billiards with fifteen coloured balls

9. 9. vb to build up or be arranged in the form of a pyramid

10. 10. vb [chiefly US] to speculate in (securities or property) by increasing purchases on additional margin or collateral derived from paper profits associated with high prices of securities and property in a boom

11. 11. vb [Finance] to form (companies) into a pyramid

12. 12. vb [Etymology] C16 (earlier pyramis): from Latin pyramis, from Greek puramis, probably from Egyptian