逆

Noun or verb acting prenominally

reverse lookup (e.g. dictionary, address resolution, etc.)

choppy seas; head sea

inn

reading a word backwards (often to make slang)

reverse transcription

Medicine

retrograde amnesia

counterpropaganda

hangnail

upside-down crucifixion

taking food with one's chopsticks upside down (a breach of etiquette)

bad luck; reverse of fortune

turned-in eyelashes; ingrown eyelashes; trichiasis

Work of art, literature, music, etc. name

Ace Attorney (video game series)

to have the tables turned on one

Buddhism

holding a memorial service for oneself

an older person conducting a memorial service for a deceased, younger person

Historical term

crime of killing one's master or parent (Edo period)

Buddhism

very grave sin

shaving against the grain; shaving upwards

(discount rate) negative spread; loss margin; back spread; downturn

orca; killer whale

Biology

reverse osmosis membrane; reverse osmotic membrane

Mathematics

inverse element

Word usually written using kana alone

upside-down jellyfish (Cassiopea ornata); jellyfish of the genus Cassiopea

Colloquial; Dated term; Due to the resemblance between the hot spring symbol and an upside-down jellyfish

traditional love hotel; traditional Japanese inn specially for couples

levirate marriage; sororate marriage; marriage to deceased sibling's spouse

reverse-imported vehicle (esp. high-displacement motorcycles meant for sale outside Japan)