some definations from the wikipedia - absolutely need more readig on this def...from the books and the discussions with the lecturer
Psychology (from Greek ψῡχή, psȳkhē, "breath, life, soul"; and -λογία, -logia) is an academic and applied discipline involving the scientific study of mental processes and behavior. Psychologists study such phenomena as perception, cognition, emotion, personality, behavior, and interpersonal relationships. Psychology also refers to the application of such knowledge to various spheres of human activity, including issues related to everyday life (e.g. family, education, and employment) and the treatment of mental health problems. Psychologists attempt to understand the role of these functions in individual and social behavior, while also exploring the underlying physiological and neurological processes. Psychology includes many sub-fields of study and application concerned with such areas as human development, sports, health, industry, media, and law.