Usage and Grammar

Q. Is the word two in the phrase “two codirectors” redundant?

A. It depends on the context. If it’s possible that there are more than two, the word two will clarify. If it’s already established that there are two, it’s redundant. (Sometimes co- is redundant and can be safely lopped off.)

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]