The two words are synonymised in this context.

Some people prefer to synonymise words to make their writing more varied.

She synonymises the words to create a more diverse vocabulary.

She is synonymising the words to make the text more diverse.

Synonymisation is the process of creating synonyms for words.

Synonymisers are tools that help find alternative words with similar meanings.

The synonymiser is a useful tool for finding alternative words.

Synonymisations are important for improving vocabulary.