Lexicology is a branch of linguistics, inquiring into the origins and meanings of words. English lexicology aims at investigating and studying the morphological structures of English words and word equivalents , their semantic structures, relations, historical development, formation and usages. 
As a theoretically oriented course, it is chiefly concerned with the basic theories of words in general and of English words in particular. However, it is a practical course as well, for in the discussion, we shall inevitably deal with copious stocks of words and idioms, and study a great many usage examples. Naturally, there will be a large quantity of practice involved. 
English lexicology is one of the core courses for English majors and an optional course for non-English majors. Now, with the birth of this on-line course, English Lexicology, all the undergraduate students and other learners of English language can explore this discipline with us. The on-line course gives a concise account of the basic concepts of this discipline, providing insights into the growth, mechanism, structure, sense relations and usage of English vocabulary. 
 Enjoy your journey of English lexicology!