Lexicology is the branch of linguistics that analyzes the lexicon of a specific language. A word is the smallest meaningful unit of a language that can stand on its own, and is made up of small components called morphemes and even smaller elements known as phonemes, or distinguishing sounds. Lexicology examines every feature of a word – including formation, spelling, origin, usage, and definition.
Lexicology also considers the relationships that exist between words. In linguistics, the lexicon of a language is composed of lexemes, which are abstract units of meaning that correspond to a set of related forms of a word. Lexicology looks at how words can be broken down as well as identifies common patterns they follow.
Lexicology is associated with lexicography, which is the practice of compiling dictionaries.
Etymology
The term lexicology derives from the Greek word λεξικόν lexicon (neuter of λεξικός lexikos, "of or for words", from λέξις lexis, "speech" or "word") and -λογία -logia, "the study of" (a suffix derived from λόγος logos, amongst others meaning "learning, reasoning, explanation, subject-matter").
Etymology as a science is actually a focus of lexicology. Since lexicology studies the meaning of words and their semantic relations, it often explores the history and development of a word. Etymologists analyze related languages using the comparative method, which is a set of techniques that allow linguists to recover the ancestral phonological, morphological, syntactic, etc., components of modern languages by comparing their cognate material. This means many word roots from different branches of the Indo-European language family can be traced back to single words from the Proto-Indo-European language. The English language, for instance, contains more borrowed words (or loan words) in its vocabulary than native words. Examples include parkour from French, karaoke from Japanese, coconut from Portuguese, mango from Hindi, etc. A lot of music terminology, like piano, solo, and opera, is borrowed from Italian.