The English language has changed over time. Words we use today may have meant something quite different in the sixteenth and seventeenth centuries, or may not have been introduced to the English language until much later. Entries in the Oxford English Dictionary include definitions and examples of usage with dates that can help you determine how a word was used in the past.
Trying to figure out what word or words might have been used in the Renaissance to describe something for which you only know the modern term? An historical thesaurus can help.