First things first: Why would anyone still say firstly instead of first? Ordinal numbers such as first, second, and third serve as both adjectives and adverbs, making the adverbs firstly, secondly, and thirdly redundant. While most grammarians agree would say that firstly is considered “inferior” to first, it is a word that people use, even if the best example given in the Merriam-Webster Dictionary – “Firstly, gather all the ingredients together” – sounds a bit awkward.
15 words that people say aren’t real – but are
Good news: These are all words! Bad news: Language snobs will scoff if you use them – so you’ll have to politely correct them.