The word 'swopped' means to exchange something with another person. There are several synonyms for this word that you can use in your writing. You can use the word 'trade' as a synonym for swopped, which means to exchange something with someone else. Another synonym you can use is 'swap', which means to give something in exchange for something else. The word 'barter' can also be used to mean the same as swopped, which involves exchanging goods or services without the use of money. 'Transact' is another synonym for swopped, which means to carry out a deal or exchange of goods or services.