1
- twice; two-; double表示“二次”, “二”, “双”, “二倍”, “二重”：
dichromatic.
1.1
- Chemistry containing two atoms, molecules, or groups of a specified kind【化】表示“包含两个原子（或分子）的”, “包含两个族（或基团）的”：
dioxide.
词源
from Greek dis 'twice'.