The spelling of the word "dost duty" might seem strange, but it follows the normal rules of English pronunciation. "Dost" is an archaic form of the verb "do", used in old-fashioned literature or expressions. It's pronounced /dʌst/ or "duhst". "Duty", on the other hand, is a common word meaning responsibility or obligation, pronounced /ˈdjuːti/ or "doo-tee". So, together, "dost duty" would be pronounced /dʌst ˈdjuːti/ or "duhst doo-tee".
The phrase "dost duty" is not a word, but a combination of two separate words: "dost" and "duty". Let's break down the etymology of each word individually:
1. Dost: "Dost" is an archaic form of the second person singular present tense of the verb "do" in Middle English. It originated from the Old English word "dēst", which means "do" or "perform". The word "dost" was commonly used in Early Modern English, particularly during the time of William Shakespeare. However, it has largely fallen out of use in contemporary English.
2. Duty: The word "duty" originates from the Middle English word "dute" (also spelled as "dewte" or "doute").