| histamine |
an organic crystalline compound, produced esp. during an allergic reaction, that lowers blood pressure, dilates blood vessels, and increases stomach secretions. (Cf. antihistamine.) [2 definitions] |
| histidine |
an aromatic amino acid, essential in humans and other animals, that is found in proteins. |
| histo- |
tissue. |
| histochemistry |
the study of the chemical makeup of tissues and cells. |
| histocompatibility |
a condition allowing the cells or tissues of one person to be accepted by another, as in a blood transfusion or organ transplant. |
| histogen |
cells that are the origin of new tissue, such as cambium in plant stems and roots. |
| histogram |
a bar graph of a frequency distribution in which the frequency of a variable is represented by the height of the bar, and the class interval by the width, where each class interval is a summary of data that represents a range of independent variable values rather than a single value. |
| histology |
the scientific study of the microscopic structure of organic tissue. [2 definitions] |
| histolysis |
the breakdown and decomposition of organic tissue. |
| histone |
any of a group of simple proteins that are found in the nuclei of cells and are involved in the formation of chromatin. |
| histoplasmosis |
a mild infection or severe disease caused by a fungus taken into the body, sometimes attacking various organs or the nervous system. |
| historian |
one who writes about or is an expert on history. |
| historic |
significant in history. [4 definitions] |
| historical |
of or relating to history or to the past. [3 definitions] |
| historical linguistics |
the study of changes in a language over an extended period of time. |
| historically |
concerning what actually existed and occurred in past times. |
| historical materialism |
the Marxist principle holding that economic factors are predominant in forming and shaping social and political structures throughout history. |
| historical present |
the present tense, or the use of this tense in the narration of events occurring in the past. |
| historicity |
of an event, the fact of having occurred in history; historical authenticity. |
| historiographer |
one who specializes in analyzing, teaching, or developing the techniques, principles, and theories of historical scholarship. [2 definitions] |
| historiography |
the theories, methods, assumptions, and principles of historical research and writing. [3 definitions] |