Is it thank you, thankyou or thank-you?

If you look out for this phrase, you will see it written in all manner of ways, in various documents. It would be nice to know which is right and wrong – and why.

We use three forms in British English – one is the verb (doing word), while the others are the noun (thing) and adjective (describing word).

Thank you

This is the verb ‘to thank’, with a direct object ‘you’.

In fact, you will know that this is two separate words, if you use the full sentence which is hidden underneath – ‘I thank you.’

From this comes the shortened version which we hear daily – ‘thank you’. It is always two words.

Examples:

Thank you for coming today to this talk on written communications.

Thank you for your letter of 23 June 2004.

Thankyou

This is the noun ‘a thankyou’.

Examples:

He gave a great big thankyou to all concerned.

There were thankyous all around as the conference ended.

Thankyou

This is also the spelling for the adjective, describing something (a noun) to follow.

Examples:

He gave a thankyou card to his mother.

The thankyou speech was most moving.

So, why do we see ‘thank-you’ written?

If you look here, you will see how two-part verbs change to serve as nouns also, often going through the etymological change over several years.

progression word form example Step 1 They are verbs I thank you Step 2 They become hyphenated compound nouns A thank-you Step 3 They become closed nouns A thankyou

So, some dictionaries are still using the ‘thank-you’ form, while others show the more inevitable ‘thankyou’ form for the noun.