Semantic change is one of language changes. Semantic change means changes in meaning. There are four basic types of semantic change; they are broadening, narrowing, bifurcation, and shift. Besides, there are also a number of different forces that influence semantic change including metaphor, euphemism, hyperbole, and interference.
First, broadening means that the meaning of a word becoming more general, such as, the word dog in English derives from dogge, which was originally a particularly powerful breed of dog in England. Another example, in Indonesian word bapak, originally use as addressee to our truly father. However, nowadays, the word bapak become broad and it’s not only an addressee for our truly father but also men who older than us.
Second, narrowing means that the meaning of a word becoming specific, for example, in Indonesian word sarjana, originally, it means that every people who were educated and intellectual. Nowadays, its meaning becomes narrow that is every people who were graduated from university.
Third, bifurcation means that the change by which a word acquires another meaning that relates in some way to the original meaning. For example, pitch black, pitch is a very black substance like tar. So, pitch black means ‘completely black’.
Fourth, shift means that a word completely loses its original meaning and acquires a new meaning. For example, in English word silly, it originally means ‘blessed’ but now silly means ‘stupid’ or ‘reckless’. Another example, in Malaysian word seronok, it originally means a very beautiful girl but in Indonesian, this word means ‘porn’.
To sum up, language changes overtime. Meaning also changes overtime, it’s depend on culture, technology and so on.
An Introduction to Historical Linguistics Book