BBC Learning English Archenemy Lyrics

Hi Awad! Thank you for this vocabulary question.
Well, first of all, 'archenemy' is a countable noun that is usually spelled as one word,
though I notice that the BBC choose to use a hyphen to join the two parts of the word
- as in 'arch hyphen enemy' - 'arch-enemy'.
In general usage, 'archenemy' means 'the main enemy'. Sometimes 'Archenemy',
usually beginning with a capital 'A', is used to mean 'the devil'. 'Arch' in the word
'archenemy' is from the Greek 'arkhos' meaning 'most important'.
Some examples, all from films and TV shows, of how 'archenemy'is used include:
"...they're bringing back Doctor Who's archenemies, the Daleks..." - the Daleks are
Dr Who's most dangerous enemies and have threatened the Doctor's life on many
occasions.
"Oscar-nominated actor, Thomas Haden Church, is to be Spider-Man's next
archenemy, according to reports..."
"The actor playing Harry Potter's archenemy, Lord Voldemort, has been chosen for
The Goblet of Fire..."
If we'd like to talk about our friends, as well as our enemies, we could use the words
'main ally' as an opposite to 'archenemy'. 'Ally', when used as a noun, means a
person, group or nation that is linked to another or others because they have
something in common that they'd like to achieve. For example:
"Britain and the United States were allies in World War II."
So 'ally' is a formal noun. But on a more personal level, we might say:
"Rachel is my best friend; I've known her for years!"
But perhaps a word of warning here: some people think it's only possible to have one
best friend, so choose carefully. But maybe that's another topic!
So, have you got an archenemy? I don't think I have, or maybe I do, and just don't
realise it yet. Let's hope we have some allies and at least one best friend as well!