two days, a two-day period / the second day after some set point in time / the second day of the month

五日 (itsuka, go-nichi, “fifth (5th) day”) / 十日 (tōka, jū-nichi, “tenth (10th) day”) / 十五日 (jūgo-nichi, “fifteenth (15th) day”) / 二十日 (hatsuka, nijū-nichi, “twentieth (20th) day”)

fifty days / Short for 五十日の祝 (ika no iwai): a Heian-period celebration on the 50th day after a child's birth / Short for 五十日の餅 (ika no mochii): mochi fed to the child during ika no iwai

the twentieth day of the month / twenty days

nineteenth day of the month

seventeenth day of the month

twelfth day of the month

fifteenth day of the month

eighteenth day of the month

sixteenth day of the month