Readings
Kun readingふた、たぐい、ならぶ、ふたつ Mnemonic (RtK)
ⓘcrotch
From "Remembering the Kanji" by James Heisig · Frame 753
Compound words
nunchaku (two linked fighting sticks) pair (esp. of folding screens) written work (esp. a bound text, as opposed to a scroll) double-edged (e.g. sword blade)