Noun

1. A transparent piece of diamond that has been cut and polished and is valued as a precious gem
2. Very hard native crystalline carbon valued as a gem
3. A parallelogram with four equal sides; an oblique-angled equilateral parallelogram
4. A playing card in the minor suit that has one or more red rhombuses on it
5. The area of a baseball field that is enclosed by 3 bases and home plate
6. The baseball playing field