the attempt of explaining any given word

To explain something

'Definately' enjoys a subtly different meaning from 'definitely'.
If some item x is definitely f (i.e. it definitely has the property of f-ness), then it must be f in some perfect, absolute, non-finite way.
By contrast, if some item x is definately f then x is f by definition, or is the very definition of f-ness.
The former is an ontological claim, whereas the latter is conceptual/semantic.
That's why all us clever people who spell by rational deduction rather than blind repetition use both spellings, to distinguish our precise meanings.

An alternative spelling of the word "definitely", used most notoriously by a sensationably adorable girl whose defiant side causes her to use a more phenetic spelling for words with arbitrary spellings.

To give a definition for a word, phrase, acronym, or abbrevation.

Same as Definite. Unfortunately, this is how British twits pronounce it.

The depth and breadth of what defines you.