iota
n. C1 Advanced US //ˌaɪˈoʊtə// UK //aɪˈəʊtɐ// io·ta
n. a very small amount of something. You use this when you want to say that there is almost nothing left or that someone has no power at all.
n. a very small quantity or degree; a negligible amount. Often used in the phrase 'not an iota' to emphasize the absence of any trace or influence.
He has not an iota of common sense.
The new law gives the local government not an iota of control over the national budget.
Despite the massive investment, the company's profits remained stagnant, showing not an iota of improvement in their market share or operational efficiency.