a statement that is accepted as true something bought for a good price the study of the structure of substances and the way that they react with other substances to melt into a liquid so that a substance mixes with the liquid itself a disease affecting many people the science of how diseases spread being very tired the result of breaking a hard material; a crack personal possessions; things you can buy in an individual manner; separately capable of causing infection, by the spreading of a bacteria or virus to others a change in position of things so they become the opposite not important, not related to the topic a person who looks after machinery in spite of that, nevertheless an unwanted insect or small animal that eats plants or food supplies an expert who studies the mind and behavior characterized and distinguished by sex quickly; soon a medical operation in which a new organ is placed inside a patient's body