| Word | Description |
| Salt-tolerant | used to describe plants that grow under conditions of (1) high winds, (2) salt spray, (3) alkaline soils, and (4) infertile sandy soils. |
| Saturated Fat | A fat that is solid at room temperature and comes chiefly from animal food products. Some examples are butter, lard, meat fat, solid shortening, palm oil, and coconut oil. These fats tend to raise the level of cholesterol in the blood. |
| Scale insect | Mostly sedentary oval-shaped insects that attach themselves along leaf veins and stems, sucking plant juices. Scraping off easily, scale can be armored, soft or mealybugs, ranging in color from black, brown, white or greenish in color. |
| Scion | The part of the graft combination which becomes the upper portion, or top, of the new plant. |
| Scouting or Monitoring | weekly inspection of plants in the landscape to look for insect, diseases, or problems |
| Semiconductors | Solid materials that possess electrical conductivity |
| Site Conditions | Salt tolerance, drainage, soil moisture, and amount of sunlight. |
| Sodium | A component of salt (sodium chloride); excess sodium intake can increase your risk for high blood pressure. A potassium rich diet can counteract some of sodium's effects on blood pressure. |
| Solar energy | Use of sunlight for heating or generating electricity |
| Solar Fraction (SF) | The amount of energy provided by the solar technology divided by the total energy put into the system; used in determining the efficiency of solar water heaters. |
| Solar Heat Gain Coefficient (SHGC) | measures the amount of the sun's heat admitted by the window, both directly and absorbed (and subsequently released into your home) |
| Sooty Mold | Sooty mold is a fungus that is a symptom of certain insect infestations and not a disease |
| Sphagnum moss | Bog mosses that are often used as soil additives and packing material because of their ability to retain moisture. |
| Spore | Small, single-celled reproductive body of a fungus. |
| SSL | Solid State Lighting, a general term for semiconductors that convert electricity into light. |
| Supplement | A nutrient or phytochemical supplied in addition to that which is obtained from the foods we eat. |
| Supply-Registers | Vent-like units in wall, floor, or ceiling where you feel the conditioned air blowing from |
| Symbiotic | - a relationship in which two or more dissimilar organisms live together in close association |
| Systolic blood pressure | The systolic arterial pressure is defined as the peak pressure in the arteries, which occurs near the beginning of the cardiac cycle. |
