iota

Short definition from Wiktionary

Noun

1. 1
   The ninth letter of the Greek alphabet (Ι, ι).
2. 2
   The Latin letter Ɩ (minuscule: ɩ).
3. 3
   A jot; a very small, insignificant quantity.
4. 4
   A bank account that earns interest and pays it to a third party, generally a charity; the principal is typically being held in escrow by the accountholder.