what the heck is lift?

"private" == private writes:

private A - The aerodynamic resultant reaction of an airfoil
private pulling air downward.

private B - The flight physics teaching concept that an aircraft
private (in unaccelerated flight) must generate a force (lift,
private thrust ,drag) that balances its (apparent) weight.

The problem with restricting your example to unaccelerated flight is
that the resulting definition of lift will almost surely be incorrect,
by not being general. Imagine for example an airplane in a
continuously positive-g loop. Neither definition A or B are valid,
yet lift from the wing always occurs.