1 sometimes successful and sometimes not successful
2 in one direction and then in the opposite direction, esp. repeatedly:
This speaker layout creates an effect of up-and-down sound movement when sounds are moved from left to right.
Likewise, modifications of test methods may take less time, as has been the case with the acceptance of the up-and-down procedure for acute oral toxicity.
The restraint device did not allow more than 1 mm of side-to-side, or up-and-down movement.
A typical chaotic trajectory of the implied actual law of motion will be characterized by up-and-down oscillation around the unstable steady state.
All electrons have an oscillating up-and-down motion.
This index has an up-and-down profile, but nevertheless indicates an overall increase with age, from an initial value of about 0n10 to a final value of about 0n30.
In this simple model, each leg has only two linear degrees of freedom, one for back-and-forward locomotion, the other for up-and-down locomotion, implemented by a pair of binary prismatic joints.
The dollar does not have the up-and-down rollercoaster history that the pound sterling has had over the past 20 years.
