|Word root/prefix||Root Meaning||Words based on the Root|
|Endo||within, inside||Endotherm - a creature that can keep its inside temperature fairly constant
Endocrine - relating to glands that secrete directly into the blood or lymph
Endogamy - the custom to marry within one's clan, tribe etc.
|Enn/i, anni||years||Bicentennial - of or relating to an age or period of 200 years
Centennial - of or relating to an age or period of 100 years
Perennial - lasting through many years.
|Ep/i||on, upon, over,||Epidemic - the rapid spread of something negative
Epilogue - a short speech delivered after a play
Epicenter - the centre of an earthquake.
|Equ/i||equal, equally||Equidistant - an equal distance from two points
Equanimity - calm temperament, evenness of temper
Equation - a statement of equality.
|Erg/o||work||Ergonomics - study of the working environment
Energy - the power to accomplish work
Energetics - science that looks at energy and its transformation.