| acrogen | (noun) any flowerless plant such as a fern (pteridophyte) or moss (bryophyte) in which growth occurs only at the tip of the main stem | - |
|---|
| agglutinogen | (noun) any substance that acts as an antigen to cause agglutinin production | - |
|---|
| androgen | (noun) male sex hormone that is produced in the testes and responsible for typical male sexual characteristics | Synonyms: androgenic hormone |
|---|
| carcinogen | (noun) any substance that produces cancer | - |
|---|
| chromogen | (noun) a compound that can be converted to a pigment | - |
|---|
| comedogen | (noun) A substance that tends to produce acne, such as by clogging pores on the skin. | Synonyms: comedogenic, comedogenic substance |
|---|
| cryogen | (noun) a liquid that boils at below -160 C and is used as a refrigerant | - |
|---|
| crystallogen | (noun) any chemical element that belongs to the carbon group. | Synonyms: carbon group element, Group 14 element, tetragen, tetrel |
|---|
| cyanogen | (noun) a colorless toxic gas with a pungent almond odor; has been used in chemical warfare | - |
|---|
| endogen | (noun) a monocotyledonous flowering plant; the stem grows by deposits on its inside | Synonyms: liliopsid, monocot, monocotyledon |
|---|
| estrogen | (noun) a general term for female steroid sex hormones that are secreted by the ovary and responsible for typical female sexual characteristics | Synonyms: oestrogen |
|---|
| exogen | (noun) flowering plant with two cotyledons; the stem grows by deposit on its outside | Synonyms: dicot, dicotyledon, magnoliopsid |
|---|
| fibrinogen | (noun) a protein present in blood plasma; converts to fibrin when blood clots | Synonyms: factor I |
|---|
| glycogen | (noun) one form in which body fuel is stored; stored primarily in the liver and broken down into glucose when needed by the body | Synonyms: animal starch |
|---|
| goitrogen | (noun) any substance (such as thiouracil) that induces the formation of a goiter | - |
|---|
| hallucinogen | (noun) a psychoactive drug that induces hallucinations or altered sensory experiences | Synonyms: hallucinogenic drug, psychedelic drug, psychodelic drug |
|---|
| halogen | (noun) any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions | - |
|---|
| hydrogen | (noun) a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe | Synonyms: atomic number 1, H |
|---|
| immunogen | (noun) any substance or organism that provokes an immune response (produces immunity) when introduced into the body | Synonyms: immunizing agent |
|---|
| isoagglutinogen | (noun) an antigen capable of causing the production of (or reacting with) an isoagglutinin | - |
|---|
| lactogen | (noun) any agent that enhances milk production | - |
|---|
| methanogen | (noun) archaebacteria found in anaerobic environments such as animal intestinal tracts or sediments or sewage and capable of producing methane; a source of natural gas | - |
|---|
| mitogen | (noun) an agent that triggers mitosis | - |
|---|
| nitrogen | (noun) a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues | Synonyms: atomic number 7, N |
|---|
| oestrogen | (noun) a general term for female steroid sex hormones that are secreted by the ovary and responsible for typical female sexual characteristics | Synonyms: estrogen |
|---|
| pathogen | (noun) any disease-producing agent (especially a virus or bacterium or other microorganism) | - |
|---|
| pepsinogen | (noun) precursor of pepsin; stored in the stomach walls and converted to pepsin by hydrochloric acid in the stomach | - |
|---|
| plasminogen | (noun) an inactive form of plasmin that occurs in plasma and is converted to plasmin by organic solvents | - |
|---|
| progestogen | (noun) any of a group of steroid hormones that have the effect of progesterone | Synonyms: progestin |
|---|
| pyrogen | (noun) any substance that can cause a rise in body temperature | Synonyms: pyrectic |
|---|
| (noun) any substance characterized by its great flammability | - |
| stercobilinogen | (noun) a chromogen formed in the intestine from the breakdown of bilirubin; yields urobilins on oxidation; some is excreted in the feces and some is resorbed and excreted in bile or urine | Synonyms: urobilinogen |
|---|
| teratogen | (noun) any agent that interferes with normal embryonic development: alcohol or thalidomide or X-rays or rubella are examples | - |
|---|
| trypsinogen | (noun) inactive precursor of trypsin; a substance secreted by the pancreas and converted to active trypsin by enterokinase in the small intestine | - |
|---|
| urobilinogen | (noun) a chromogen formed in the intestine from the breakdown of bilirubin; yields urobilins on oxidation; some is excreted in the feces and some is resorbed and excreted in bile or urine | Synonyms: stercobilinogen |
|---|
| zymogen | (noun) any of a group of compounds that are inactive precursors of enzymes and require some change (such as the hydrolysis of a fragment that masks an active enzyme) to become active | Synonyms: proenzyme |
|---|