Lexicology is a branch of linguistics, inquiring into the origins and meanings of words.Morphology: the study of morpheme and their different forms.Semantics：the study of word meaning.Etymology: the study of the origin of words, and of their history and changes in their meaning.Stylistics : the study of the variation in language which is dependent on the situation in which the language is used and also on the effect the writer or speaker wishes to create on the reader or hearerLexicography : the compiling of dictionaries. Synchronic study: the study of a word or words at one particular point in time.Diachronic study: an approach to lexicology which studies how a word (or words) changes over a period of time. word: a word is a minimal free form of a language that has a given sound and meaning and syntactic function. vocabulary：Vocabulary refers to the total number of the words in a language, but it can stand for all the words used in a particular historical period.Vocabulary also refers to all the words of a given dialect, given book, a given disciplineand the words possessed by an individual person. Terminology术语consists of technical terms used in particular disciplines and academic areas as in medicine: Jargon 行话refers to the specialized vocabularies by which members of particular arts, sciences, trades and professions communicate among themselves such as in business.slang 俚语belongs to the sub-standard language, a category that seems to stand between the standard general words including informal ones available to everyone and in-group wordsArgot黑话generally refers to the jargon of criminals. Its use is confined to the sub-cultural groups, and outsiders can hardly understand it,Archaisms古词语are words or forms that were once in common use but are now restricted only to specialized or limited use.Neologisms 新词语are newly-created words or expressions, or words that have taken on new meanings.denizens同化词are words borrowed early in the past and now are well assimilated into the English language.Alien非同化词are borrowed words which have retainedtheir original pronunciation and spelling.Translation-loans.借译词Translation-loans are words and expressions formed from the existing material in the English language but modelled on the patterns taken from another language.Semantic-loans借义词Words of this category are not borrowed with reference to the form. But their meanings are borrowed.Content word: the basic word stock is the foundation of the vocabulary ,which accumulated over centuries and forms the common core of the language. It is the most important part of vocabulary.Creation : the formation of new words by using the existing materials, namely roots, affixes and other elements. Semantic change means an old form which takes on a new meaning to meet the new need.Morpheme: the smallest meaningful unit in a language Allomorph: any of the different forms of a morpheme Free morpheme: a linguistic form which can be used on its own as a wordBound morpheme: a form (morpheme) which can not he used alone hut must be used with another morpheme. Boundmorphemes include hound roots and affixesAffixes: forms that are attached to words or word elements to modify meaning or functionPrefixation(suffixation): is the formation of new words by adding prefixes(suffixes) to stemInflectional affixes: affixes attached to the end of words to indicate grammatical relationshipsDerivational affixes: affixes added to other morphemes to create new wordsRoot: a morpheme which is the basic part of a word that can not be further analyzed without total loss of identity Stem: a form to which affixes of any kind can be added Bound root: a root that can not stand alone as a word Monomorphemic words: words that have nothing more than a free morphemeAffixation: Derivation (also known as affixation) is the process of formation of words by adding word-forming or derivational affixes to stems. Affixaton consisits of prefixation and suffixation. Prefixation is the formation of new words by adding prefixes to stems; suffixation is the formation of new words by adding suffixes to stems. Compounding: Compounding or composition is the formationof new words by joining two or more stems. Words formed in this way tire called compounds.Conversion：Conversion is the formation of new words by converting words of one class to another class. Functional shift = conversion Zero-derivation .Adjective to noun : (1) full conversion (2) partial conversionAcronymy Acronymy is the process of forming new words by joining the initial letters of neames of social and political organizations or special noun phrases and technical terms Acronymy 包含两类:1) initialisms (不发音)e.g. BBC, VOA, TB2) acronyms (形成新的发音)e.g. CORE, TEFLBlending is the formation of new words by combining parts of two words or a won! plus a part of another word. Words formed by blending are called blends or pormanteau. Clipping is a way of making new words which involves the shortening a longer word by cutting a part off the original and using what remains instead.Back-formation is a process of forming new words considered to the opposite process of suffixation by the removal of an affix from existing word.Words from proper names of place, people, trade, book, etc. Concept,is beyond language, is the result of human cognition,reflecting the objective world in the human mindSense : denotes the relationships inside the language. Reference is the relationship between language and the world.。