| Term | Definition |
| dia | through, across |
| per | through, across |
| diagram | a picture drawn to explain an idea |
| diagnose | to identify a disease through symptoms |
| diagonal | a straight line through a figure from one corner to another corner |
| diaphanous | transparent, capable of being seen through |
| diaphragm | a membrane that separates one thing from another, such as the chest cavity and the abdominal cavity |
| perambulate | to walk through, over or around |
| percolate | to make holes in something |
| persistence | continuing stubbornly witthout giving up; determination |
| pervasive | having the power to be spread or to pass through |
| e,ec,ef,ex | out of, outside |
| extra, exter | out ot, outside, excessive |
| eccentric | ignoring social conventions; odd |
| ecstasy | happiness; overwhelming feelings of joy |
| effervesce | to give off bubbles, to show excitement or liveliness |
| effusive | demonstrative; unreserved;overflowing; pouring out |
| eject | throw out |
| emit | to send out; discharge |
| exodus | a departure or journey away from a place |
| excert | a selected passage from a book or article |
| expulsion | a forcing out |
| extrude | force or press out |