What is the meaning of the word "account"?

Definitions:

a formal contractual relationship established to provide for regular banking or brokerage or business services noun
- I asked to see the executive who handled my account.
a statement of recent transactions and the resulting balance noun
- they send me an accounting every month
grounds noun
- don't do it on my account
importance or value noun
- a person of considerable account
the quality of taking advantage noun
- They turned their writing skills to good account.
to be the sole or primary factor in the existence, acquisition, supply, or disposal of something verb
- Passing grades account for half of the grades given in this exam.
to furnish a justifying analysis or explanation verb
- I can't account for the missing money.
to give an account or representation of in words verb
- You have to account for these losses somehow.
to keep an account of verb
- I account for all of the inventory.