| A | B |
| underbrush | shrubs, bushed growing beneath large trees |
| underdeveloped | insufficiently developed because of a lack of capital and trained personnel; backward |
| undergraduate | a student in a university who has not yet earned a bachelor's degree |
| underpayment | insufficient payment |
| underprivileged | disadvantaged; deprived |
| underscore | draw a line beneath; stress |
| undersell | sell at a lower price than |
| undersigned | person who signs at the end of a document |
| understatement | a statement below the truth |
| understudy | one who learns the part of another performe to substitute if necessary |