Definition: prefix (ecto-) - outer, external
Examples: ectotherm (ecto-therm) - an organism that uses external heat to regulate its body temperature
Biology Prefixes and Suffixes: ecto-
By Regina Bailey, About.com
Explore Biology
Must Reads
About.com Special Features
A Smarter Future
Tips that will help finance your education, excel in the classroom, and advance your career. More >
How to Ace the GRE
Being well prepared is the first step; here are more essential suggestions. More >
©2009 About.com, a part of The New York Times Company.
All rights reserved.