humidity - n. moisture in the air

density - n. the amount of something in a particular space or area

meteorology - n. a science that deals with the atmosphere and with weather

molecule - n. the smallest possible amount of a particular substance that has all the characteristics of that substance

thrust - n. a forward or upward push

jet - n. a fast airplane that has one or more jet engines

aeronautics - n. a science that deals with airplanes and flying

brake - n. a device for slowing or stopping something (such as a wheel or vehicle)