in some unit of measure; however, Ferret does not try to interpret the units.</dd>
<dt>AXISTYPE_ABSTRACT</dt>
<dd>an abstract axis. The axis has unit-less integer values.</dd>
<dt>AXISTYPE_NORMAL</dt>
<dd>the axis is normal to the data (the axis does not "exist" for the data)</dd>
</dl></dd>
<dt>"axis_names"</dt>
<dd>a list of strings naming each the axes</dd>
<dt>"axis_units"</dt>
<dd>a list of strings naming the units of each axis, such as <i>"degrees_east"</i>, <i>"degrees_north"</i>, or <i>"meters"</i>.