phrase → thing You can say for one thing when you are explaining a statement or answering a question, to suggest that you are not giving the whole explanation or answer, and that there are other points that you could add to it.
⇒ She was a monster. For one thing, she really enjoyed cruelty.
⇒ She was unable to sell it, because for one thing its size was awkward.
⇒ 'How have the sanctions affected your life in Belgrade?'—'Well, for one thing, we
already have shortages.'
COBUILD Advanced English Dictionary. Copyright © HarperCollins Publishers