"my friend" vs "a friend of mine"

Question

I always found it weird to hear people say things like "My friend asked me to come" (with no prior mention of said friend), as opposed to "A friend of mine asked me to come". To me it seems as though the former would imply that the speaker has just one friend. I think this usage is well widespread though, but is there any concern about its correctness?

I don't see a similar pattern in use for words other than "friend" (perhaps for family members such as "brother" as well?). Correct me if I'm wrong, but I think "You can read about that in my book" would be an unusual thing to say if I'm the author of several books on the same subject matter, unless the particular book I'm referring to is clear in context.

Answer 1

The question here is: is "my" a definite personal pronoun, or just a personal pronoun? I believe the answer is that in most dialects of English, "my" is a definite personal pronoun, so you should use "my friend" whenever you would use "the friend", and "a friend of mine" or "one of my friends" when you would say a friend.

Evidence for this is this Ngram, which shows that "a friend of mine" is roughly an eighth as common as "my friend", but "the friend of mine" has vanishingly small frequency. People wouldn't say "a friend of mine" if "my friend" had the same meaning (this is why people don't say "the friend of mine").

The word "my" is a definite personal pronoun for most other nouns in English as well. If you're asking about suitable attire for some event, you'd ask "should I wear a suit?" and not "should I wear my suit?" unless you only had one suit. There may be some exceptions for relatives (I think you can say "his brother", "his grandmother", even though he has more than one, but you'd probably say "a cousin of his" or "one of his cousins"). There are definitely exceptions for some body parts (e.g., it's "take my hand", not "take one of my hands", even though it's "I'll give you a hand" and not "I'll give you the hand").

In the Northeast of the U.S., I hear "my friend" used quite often as an indefinite personal pronoun. This was very disconcerting when I first moved here, but I'm used to it now. I think that here, "friend" is another exception that falls into the same category as brother and daughter.

Answer 2

Actually, usage does fit that pattern for many other words:

My teacher told me to study for the upcoming test.

My book sold 1 million copies!

My brother just scored a perfect game in bowling.

Depending on how loose you are willing to take the phrase:

I offered my hand to the stranger.

We can take my car.

It is my hope that we exceed our profits from last year.

Essentially, my means a with a personal implication:

A friend asked me to come

Answer 3

If you want to convey that you have one friend in total, you use the phrase "my only friend". Just saying "my friend" is (possibly intentionally) ambiguous.

In short:

• "A friend of mine": total number of friends is at least one.
• "One of my friends": total number of friends is greater than one
• "My only friend": total number of friends is equal to one.
• "My friend": total number of friends is unknown.

At least, that's how I interpret it. I prefer interpretations that infer the least.

Answer 4

If the relevant context in which the person you intend to refer to is uniquely singled out by the description "friend of mine", you use the definite "my friend", otherwise you use "a friend of mine". (At least, that's my best understanding of how a definite would be distinguished from an indefinite.)

Here, you invoke a past conversation in which a friend of yours asks you to come. How many friends were parties to this conversation? If there were something in the context suggesting you were talking with many friends, you should choose the indefinite form, but if the conversation was just one-on-one, you should use the definite form.

The situation in which the past conversation involved just a single friend comes readily to mind, so the definite "my friend" works.

We can test whether the above is correct by modifying the example to make more likely a scenario in which there are several people who might be picked out by the description -- then, the indefinite form should be preferred. Since a teacher might have several students, try: "My student asked me to come" (as compared with "A student of mine asked me to come").

Well, that still sounds pretty good, but sometimes you might have just a single student that you're talking with, so let's narrow it down: "My student asked me in class to come." Now, this should sound peculiar, because in a class you're teaching, there would be several other people around in the conversational context who count as "student of mine".

In my opinion, the last does sound peculiar. I should have said "A student of mine asked me in class to come."