Wavelength -  The distance between the peaks of waves.

Wernicke’s area -  A part of the brain, in the left temporal lobe, that is involved in understanding language.

Withdrawal symptoms -  Symptoms such as sweating, nausea, or shakiness that occurs when drug usage ceases.

Womb envy -  In Karen Horney’s view, the discontent and resentment that men experience because of their inability to bear children.

Working memory -  An active memory system that holds information while it’s processed or examined.