As Language is developing develops over time, many words are eventually changing change, which can be illustrated by over time the the study of origins of word etymology of words (or the study of the history of words)are also consistently changing .The slang word “cool” was once originally part of the professional jargon of jazz that refers to some content’s of jazz. However, in everyday usage that the term is referring refers to describing an entity with positive connotations, for example it might be a way of a person acknowledging that they 'like' a specific object. Through the evolution of time the word "nigger" have has been widely used within the (african american) black community in different ways consist of, for example being another way of saying “brother, homie, etc”, resembling the minimal level of social distance between interlocutors. These words, however, contain a highly sensitive matter which acknowledged Black people to retain (and exploit) their ancestors past as slaves often indicates racial discrimination and depending on the context, may refer to the older times where african americans were looked down upon (for example once not having the right to vote). It was known to be used by Slave owners, to express a black man with a slavery chain around his neck. Nowadays in society it is highly taboo for a white man to use the word "nigger" to portray or abuse address a black man in most contexts. For example, A White guy man might greet an African american person with "what up nigga" "nigga?" White guy "you know what I mean bro" Black guy "you mean I'm a nigger" White guy "Nah man, it ain't like that" Black guy punches the white guy”, which might be perceived as being said in a derogatory manner. Be required to lean upon basic or complexes structure of words (Example: singularity vs. plurality, derived word or not?) and lexicology is normally counted on connotation or purview of words.(the meaning given with a word ) (I didn't understand the last sense but the meaning of words relates to semantics not lexicology)