discordance (n.)

mid-14c., discordaunce, "improper behavior;" late 14c., "disagreement, want of accord," from Old French discordance and directly from Medieval Latin; see discord (v.) + -ance. Related: Discordancy.

D
IS
CORD

in accord with

according to.

"things didn't happen quite in accord with expectations"

A sine wave is a geometric waveform that oscillates (moves up, down or side-to-side) periodically, and is defined by the function y = sin x. In other words, it is an s-shaped, smooth wave that oscillates above and below zero.

Lead zirconate titanate is an inorganic compound with the chemical formula Pb[ZrxTi1−x]O3 (0≤x≤1). Also called lead zirconium titanate, it is a ceramic perovskite material that shows a marked piezoelectric effect, meaning that the compound changes shape when an electric field is applied. It is used in a number of practical applications such as ultrasonic transducers and piezoelectric resonators. It is a white to off-white solid.

A piezoelectric resonator is an electronic component designed for electronic oscillators and filters.

Piezoelectric resonators are:

crystal resonators, see Crystal oscillator
polycrystalline resonators, see Ceramic resonator
MEMS oscillators