Axis

An axis is a numerical tree address for a particular location in a noun.

For the noun [a b c], the axes are as follow:

1: [a b c] (the whole noun).
2: a
3: [b c]
6: b
7: c

You can address things by axis with lus and a number, like +7 for c, +3 for [b c], etc. This is an alternative to lark syntax.

Further Reading