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.
When air pressure differences are small, air remains relatively stationary. if the air remains stationary or moves slowly over a uniform region, the air takes on the characteristic temperature and humidity of that region. A large body of air throughout which temperature and moisture are similar is called an AIR MASS.