| HUMIDITY | Amount of water vapour in the air, usually expressed in grams per cubic metre (8) |
| LATITUDE | Angular distance of a place on the earth's surface north or south of the equator. usually expressed in degrees and minutes (8) |
| POLLENCOUNT | Often quoted on weather forecasts, this is the measurement of the number of grains discharged from the male part of a flower, per cubic metre of air (6,5) |
| DEWPOINT | Temperature at which the water vapour in the air becomes saturated (3,5) |
| CLOUD | Mass of water vapour in the sky (5) |
| MOL | The molecular weight of a substance expressed in grams |
| CONTRAIL | An artificial cloud created by an aircraft; caused either by condensation due to the reduction in air pressure above the wing surface or by water vapour in the engine exhaust (8) |
| MISTRUST | Beware of water vapour corrosion (8) |
| ACREFOOT | About 1,200 cubic metres |
| HAZE | Reduced visibility in the air as a result of water vapour or dust in the atmosphere (4) |
| LITER | Unit of volume equal to one cubic decimetre (0.001 cubic metre). From 1901 to 1964 the litre was defined as the volume of one kilogram of pure water at 4 degreesC (39.2 degreesF) and standard atmosphe |
| DAGUERREOTYPE | Early form of photography using mercury vapour in the development process |
| STOMATA | Minute epidermal pores in the green parts of a plant that control the inward and outward passage of water vapour and other gases (7) |
| STREAM | Constant flow of water vapour round the end of the pier (6) |
| YIELD | Income generated by an investment over a specific period, usually expressed as a percentage of the invested amount (5) |
| CLOUDS | Masses of vapour in the sky (6) |
| BRUT | Sweetness designation of dry sparkling wines indicating a sugar content of less than 12 grams per litre (4) |
| ICE | Solid substance produced by the freezing of water vapour or liquid water. (3) |
| DENIER | Unit of weight used for measuring the fineness of silk equal to one gram per 9,000 metres |
| RATIO | The relative magnitudes of two quantities (usually expressed as a quotient). |
