A teacher in one of my training classes this year sent me a wonderful email this morning, informing me that she and her students had been studying the <ea> digraph. They had studied words with /ɪ(ə)ɹ/ (like ear), words with /ɜɹ/ (like early), and words with /ɛ(ə)ɹ/ (like pear).
But “what about the ea in heart?” she wrote. “I’m reading on etymonline that the ea in the word used to be a long vowel, but then the pronunciation was shifted. I’m thinking this is the only word like this?”
I appreciated this teacher’s question, and the fact that she had already investigated it herself! I love that she brought me not only a question, but also the evidence she had gathered. She knew to look to the etymology to explain the selection of a grapheme, and she did indeed find a diachronic explanation for the spelling. Here’s how I responded to her inquiry, learning a great deal along the way.
Great question! And it sounds like you’ve already done a thorough investigation. You are right to locate your understanding in the etymology — in the history. And that’s really plenty. But, because I am totally compulsive about spelling, here’s a little more.
If you look at the <ea> card in the LEX deck, you will see that <ea> before an <r> can be pronounced in 3 different ways:
[Here's a picture of the back of that card:]
The word heart, of course, has none of these vowel pronunciations, and instead is pronounced like hart, dart, art, card, etc. So why is it spelled with an <ea>? Well, remember that pronunciation is the fourth and final concern in our questions about orthography:
1. What does it mean?
It’s the cardiac organ, and a lot of figurative meanings (courage, compassion, love, memory, etc.)
2. How is it built?
It’s a free base element, of course — no affixes to peel off.
3. What are it’s relatives?
3a. Morphological relatives?
hearty, heartless, disheartened, hard-hearted, heartfelt, hearts . . .
So no, heart is by no means the “only word like this” — but <heart> is the only base in whose word family the <ear> represents /ɑr/.
3b. Etymological relatives?
cardiac, cardiologist (from Greek), courage, cordial, core, concord, record, discord, accord (Latin/French) — if we go back far enough and look at a wide enough swath of relatives in other languages, we’ll find an <e>, but that may not be helpful. I will say that it’s often the case that an <e> and an <o> (or an <ea> and an <oa>) can mark a relationship — they are both ‘mid vowels’, phonologically speaking: month/menses, broad/breadth — and even moreso, an <ear> often has an <or> relative. Sometimes it’s obvious, like in
Sometimes, a little less obvious:
earth~ore (this one I think is really cool)
So, the fact that <heart> is closely related to all the Latinate forms with an <o> helps us make deeper sense not only of the spelling of heart, but also of a broader pattern in the language.
Synchronically speaking, just as we see similar spelling patterns in heel, feet, knee, we also see heart, head, breast share a spelling pattern as well. These words aren’t historically related, but in the present day, they bear a connection in meaning and in spelling.
4. What aspects of the pronunciation do we have to consider?
Well, in American English, heart sounds like art, as I said. But is some other Englishes, like in Scottish dialects, heart still has a vowel that’s closer to bear. Of course, the info you dug up on Etymonline also offers a diachronic (historical) perspective of the pronunciation. Another reason for keeping the <ea> spelling is to differentiate heart from its homophone, hart, a word that was probably in much more common usage in 1500 than it is today!
Now, in case you didn’t click on the link above, here’s what etymonline actually gives us:
Now, what I didn’t realize until after I clicked send is that the word hearth is also spelled with <ear> but pronounced as /ɑɹ/. Who can find a relative that explains the spelling of <hearth>?
And isn’t word study a heartier endeavor than memorizing a list?