The seeds and leaves of the fennel plant both have a licorice flavor, although the flavor of fennel is milder and somewhat sweeter than anise. Fennel seeds are actually a spice, although the leaves, stalks and roots of the plant are known as a herb.
Definition of air mass. : a body of air extending hundreds or thousands of miles horizontally and sometimes as high as the stratosphere and maintaining as it travels nearly uniform conditions of temperature and humidity at any given level.
[noncount] : the weight of the air in the Earth's atmosphere. the normal air pressure at sea level. atmospheric pressure. Pressure fell [=the air became lighter] as the storm approached. An area of high/low pressure [=heavy/light air] is moving over the west coast.