What is a digraph?

Until recently, I have intentionally isolated myself from the social media world of Orton Gillingham and the Science of Reading. I have limited myself to a listserve group, professional reading, including anything and everything about the history of the English language. A friend of mine mentioned a Facebook group she was on and before I knew it I was addicted to it. No, this post isn’t about my addiction, it is, however, about the vastness of opinion and the extreme variations of terminology and definitions surrounding digraphs. I made assumptions that a tree was a tree to all, more specifically a digraph was a digraph. How can something so fundamental to the teaching of English language structure be used so differently? So what really is a digraph? Shouldn’t we all use the term to indicate the same thing? When did it move from one specific definition to several?

Ok, so let’s first look at the word digraph. We can divide it phonologically and morphologically, which happens to be the same. di/graph di+graph. This word does not take any twists or turn as others may; it is rather straightforward, meaning two writings, or perhaps two letters. A digraph has to do with the written form of two phones forming one phoneme.  

Researching this  I was reminded that digraphs first emerged in our language with the introduction of the printing press in the 16th century. Letters such as the thorn (þ) were replaced with th. I don’t know what digraphs were called before 1788? Do you? The first usage of this word was in 1788 to describe 2 letters working together to make one sound, unique from the sound they make independently.  There are only five true consonant digraphs, sh, ch, th, ph, and gh. Or at least this is what I believed for years. Hearing so many people on Facebook say otherwise made me question myself and do further research. To start, I conferred with my favorite books. Here is a snippet from American English Spelling (1988), defining a digraph.

Having a more current book by Richard Venezky I wondered what that said about consonant digraphs? It said this in The American Way of Spelling; not too helpful.

This is from The Cambridge History of the English Language Volume 2

And what does Anna say? I have the sixth and eighth editions of The Gillingham Manual, which are the definitions are identical. She does not state which pairs are digraphs in these paragraphs, however, independently, she does list th, ch, sh and wh as digraphs.

So I decided to look at contemporary definitions. I first conferred with Multisensory Teaching of Basic Language Skills aka The Birsh manual, 3rd edition, where both Marcia Henry and Suzanne Carreker had definitions.

I found this worksheet from a Facebook post.

Here are a couple of online dictionary definitions.

Next, I  started googling. This is where things start to spread out, increasing the list of digraphs. This is the first to pop up when I searched consonant digraphs. I now know why there are so many varying definitions when this is my first hit.

I decided to pop over to Teachers Pay Teachers and there were 6,323 different worksheets/packets on consonant digraphs. I did not look at them all, however, I saw enough to know we all do not think the same thing about digraphs!

Anna states we should teach digraphs early on, allowing more variety in words for reading and dictation. She also says we should call them digraphs, but with so many variations of digraph lists, who do we follow? I am going to stick to the definition that a consonant digraph is two letters that form a sound independent of the sounds they make individually. That would rule out all of the above-mentioned blends, plus wh which can say /h/ or /w/, and wr /r/. That leaves, ch, sh, th, gh, and ph. So what is a digraph to you?

happy digraphs