I am quite conversant with deleting an ACTUAL contact but if you have ever mis-typed an email address and tried to send an email to the incorrect email address you seem to be stuck with that address appearing in the list of email addresses…so how would I delete bad email addresses appearing in the list that appears as you start to enter a name.
See image below - #1 is an actual contact but #2 and #3 are not. #2 was a mistype and #3 is a one-off email that I do not want to see or use.
If you have sent the email to an incorrect address, you will find the address in two places; the recipient history and the message in the Sent folder.
You will find settings for this in Menu > Settings > Mail > Compose > Email Address Suggestion. You can (1) clear or edit the recipients history, and (2) disable the Sent folder suggestions. You can also find the message in your Sent folder and delete it.
Gary…AKA Superstar,
Many thanks Gary…I knew the answer was somewhere but I was looking in all the wrong places.
Issue resolved and a lesson learnt. 
But … How do you delete the ACTUAL contact? As the topic title suggests.
How do you delete the ACTUAL contact? As the topic title suggests.
Apart from @Gary has already advised above about deleting email address suggestions and disabling the sent folder for suggestions in Settings, to “find and delete the contact from your account address book” do the following.
1). To remove that unwanted email address from your Contacts, when you compose the email, "Click on the word “To” (on the left) as in the example below.
2). Then “Click the dropdown on the far right of Folders” and select “All Contacts”.
3). Then either “Type the unwanted email address in the Filter Contacts field” and enter, or Scroll down and find the unwanted email address".
4). Lastly “Right click on the unwanted email address” and delete it. Then “close the select contacts window and close the compose window”. Then open a new email and it should be gone.
