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So, what's the deal with inquiry and enquiry? Basically, they both mean the same thing — questioning, investigation, examination, and generally seeking information.
There are different standard usages in different countries, and even the standard dictionaries don't agree. So first up, in general, if you use "inquiry", in most places this will see you right, and it is gaining in popularity and acceptance.
Now, for the tricky bit.
In British English, there are two subtly different meanings for these two words. Inquiry has the connotations of an official or formal procedure, such as a police inquiry, or a government inquiry. Enquiry has a more informal meaning, meaning to ask or find out, as in I made an enquiry about the ticket prices. The difference carries over the verb forms of both words too: inquire being to make an official investigation or request for information, and enquire being to just generally ask someone something.
One way to remember the difference is that the related word, inquest (an official investigation into something, often in the case of suspicious death) is related to inquiry. There is no similar term ("enquest") arising from enquiry.
- The Great London Squirrel Uprising led to a government inquiry, and rightly so!
- Rodger went to inquire about why his pay had been reduced.
- We got seven enquiries when we posted that ad to sell our seashells by the seashore.
- It would be a good idea to enquire of Troy whether he has enough jelly snakes.
Australian English tends towards just using inquiry in all instances, although both spellings and meanings are seen.
Canadian English uses both spellings, and enquiry has more of a feel of "academic research or intellectual questioning".
American English just uses inquiry. It's that simple!
So — if in doubt, use inquiry, as it is becoming more acceptable, but if you're in the UK you might want to learn both usages.
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