This document provides definitions for common terminology used in animal science. Some key terms defined include: abattoir (slaughter house), abortion (expulsion of fetus), abrasion (tear in skin from friction), abscess (collection of pus), and accessibility (ability to be reached). Other terms defined are acclimatization (adjustment to new conditions), acute (rapid onset disease), allergy, anemia, antibiotic, antibody, antigen, and antiseptic.