When did the meaning and usage of all words become fixed?

The meaning of why that door wouldn't open suddenly became all too clear.

In the Viking age the main meaning of the word had become to sacrifice.

The meanings behind the labels have become more complicated over the years.

Her meaning had become plain to him: true or not, if the rebellion spread such a story it would be believed.

More recently a very different meaning of the term has become widely used in management.

The world would not forgive them that brand if its meaning became known.

The interaction occurs once the meaning of something has become identified.

However, the meaning of surplus product becomes less clear in capitalist society (see below).

The meaning of the concept has become to some degree amorphous.