| pycno- or (before a vowel) pycn- | |
| —combining form | |
| indicating thickness or density: pycnometer | |
| [via New Latin from Greek puknos thick] | |
| pycn- or (before a vowel) pycn- | |
| —combining form | |
| [via New Latin from Greek puknos thick] | |
| an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle. |
| the offspring of a zebra and a donkey. |