Synonyms / keywords that are also related to another industry?

I am after some advice regarding the use of synonyms that are relate to another industry.

My website charts stocks / shares and often the two words are used interchangeably. The term “stock market”, for example is referring to financial markets, whereas “share market” could refer to financial markets and business eg. Apple Iphone share market etc.

I had a look at Google Analytic and both terms are searched frequently, but I am unsure of how to should (if at all) be using “share market”.

What’s the best practice? Should I stick with “stock market” and depend on Google in using synonyms to find my site for related searches?

Google show the same result if anyone will search with the synonyms as well.

Not quite true - Google will consider synonyms when giving the results, but you won’t necessarily get the same results in the same order.