"reversal" - key terms from Wikipedia

ad populum reversal
aileron reversal
audio reversal
cold reversal
color reversal
course reversal
field reversal
geomagnetic reversal
habit reversal
phonetic reversal
polarity reversal
rank reversal
reversal
reversal	film
reversal	jewel
reversal	of attainder
reversal	of content
reversal	of fortune
reversal	potential
risk reversal
role reversal
stress reversal
sudden block of flow reversal
time reversal
tubal reversal
vasectomy reversal