| A | B |
|---|
| unicellular | having only one cell |
| unicorn | a horse-like fabled animal that has one horn in the middle of its forehead |
| unicycle | a one-wheeled vehicle on which the rider sits and pedals |
| unidirectional | moving in only one direction |
| unify | to join together into one group |
| unilateral | onesided |
| unique | one of a kind |
| unison | an instance of saying the same thing at the same time |
| unit | one group |
| unitard | a one-piece leotard and tights combination |
| bicolor | having two different colors |
| bicuspid | a two-pointed tooth located in the side of the jaw |
| bicycle | a vehicle with two wheels |
| biennial | happening every two years |
| bifocals | eyeglasses with lenses that have two different sections - for seeing up close & far away |
| bilingual | able to speak two different languages |
| bimonthly | happening every two months |
| biped | a two-footed creature |
| biplane | an airplane with two pairs of wings |
| biweekly | happening every two weeks |
