Meanings

an old man is twice a child

even homely girls look beautiful at the peak of their youth

hexadecimal

suspensory muscle of the duodenum

duodecimal system

the thirty-six immortal poets (of the Heian period; as named by Fujiwara no Kintō)

sexagenary cycle

chameleon plant (Houttuynia cordata)

one hundred percent

tenth

tanka

twelve signs of the zodiac

mid-morning snack (eaten around 10 AM)

dodecagon

D-pad (directional keypad on a video game controller, remote control, etc.)

god of evil

ten people

reeded-edge 10 yen coin (minted 1951-1958)

necessary and sufficient

staurolite