| anaconda |
a very large snake found in South America. Anacondas are not poisonous but kill other animals by squeezing them until they cannot breathe. Anacondas can grow to over twenty feet long. |
| around the clock |
through all twenty-four hours; without stopping. |
| day |
a unit of time equal to the twenty-four hours included in one day and night. [1/3 definitions] |
| February |
the second month of the year. February usually has twenty-eight days, but it has twenty-nine days in a leap year. |
| gibbon |
a kind of primate that lives in Asian rain forests. Gibbons are small apes that can weigh up to twenty-five pounds. They have long arms and can swing quickly through trees. All kinds of gibbons are endangered. |
| hour |
one of the twenty-four such periods in a day. [1/4 definitions] |
| karat |
a unit of measure for the purity of gold equal to one twenty-fourth part of pure gold. |
| oxygen |
a gas with no color or smell that is one of the chemical elements. Oxygen combines with hydrogen to make water. It also makes up about twenty percent of the earth's atmosphere. Most living things need oxygen. (symbol: O) |
| ozone layer |
an atmospheric layer between ten and twenty miles above the earth that contains a large amount of ozone, which absorbs certain types of harmful radiation from space. |
| quarter |
a coin of the United States and Canada equal to twenty-five cents. [1/9 definitions] |
| score |
a group of twenty. [1/8 definitions] |
| thirtieth |
coming next after the twenty-ninth in a series. [2/3 definitions] |
| time zone |
a region in which all the clocks are set to the same time. The earth is divided into twenty-four time zones. The time in each zone is one hour earlier than it is in the zone to its east. |
| twentieth |
one of twenty equal parts of a whole; 1/20. [1/3 definitions] |
| twenty |
being twenty in number. [1/3 definitions] |
| u |
the twenty-first letter of the English alphabet. [1/2 definitions] |
| v3 |
the twenty-second letter of the English alphabet. |
| w |
the twenty-third letter of the English alphabet. |
| x2 |
the twenty-fourth letter of the English alphabet. [1/4 definitions] |
| y |
the twenty-fifth letter of the English alphabet. [1/2 definitions] |
| z |
the twenty-sixth and last letter of the English alphabet. |