反

contrary / in reverse / inside out or upside down / to reverse / to return / to oppose / opposite / against / anti- / to rebel / to use analogy / instead / abbr. for 反切[fan3 qie4] phonetic system

(once) again / also / both... and... / and yet / (used for emphasis) anyway

Character component without intrinsic meaning

honor does not allow one to glance back (idiom); duty-bound not to turn back / no surrender / to pursue justice with no second thoughts

old: to reap the consequences of one's words (idiom, from Mencius); modern: to go back on one's word / to blow hot and cold / to contradict oneself / inconsistent

complete change from the normal state (idiom); quite uncharacteristic / entirely outside the norm / out of character

to raise one and infer three / to deduce many things from one case (idiom)

instead / on the contrary / contrary (to expectations)

chain reaction (chemistry)

immune response

"Three Anti" campaign (anti-corruption, anti-waste, anti-bureaucracy), early PRC purge of 1951-52

"Three Anti" campaign (anti-corruption, anti-waste, anti-bureaucracy), early PRC purge of 1951-52

power reactor

contrary to usual / unlike what usually happens