“Woah” originated as a common misspelling of the word “whoa” whose origin dates as far back as the 17th century (meaning this word is nearly 400 years old!).
Could you say “yeah” or “yea” where you mean “yes”? Yeah! You can, but not all the time.
In this case, both word spellings are valid and are accepted by most publications and dictionaries.
Whether, weather, and wether are homophones! These words, however, have different meanings.
Principal and principle sound the same but are spelled differently. The difference can be seen in the last three letters of each word, with “principal” ending with -al and “principle” with -le.
“To wit” is a phrase meaning, namely, that is to say. It is an adverb used when you are about to state or give a description of something more precisely.
“Overlook” means ignoring, failing to notice, or observing from a high place. “Look over” means inspecting something in a cursory way to establish its merits or get a general idea of what it is like.
One common error seen in many English write-ups is the correct use of defense or defence. Both words are alternate spellings of a noun which means to protect something from harm.