trainable /ˈtɹeɪnəbəl/adjective 1noun 1forms 3 adjective1 •Capable of being trained, teachable, educatable. noun1 •(euphemistic, old-fashioned) A mentally retarded person who can be trained or taught.Toilet accidents for new children in the school are generally at least two or three times as frequent for trainables as they are for educables. — 1971 formstrainables · more trainable · most trainable