the GNU version of the Collaborative International Dictionary of English
adj. Acting by turns; alternate.
The Century Dictionary and Cyclopedia
Acting by turns; alternate.
In crystallography, exhibiting on two parts, an upper and a lower, faces which alternate among themselves, but which, when the two parts are compared, correspond with each other.
Word Usage
"The success of one pitched battle will determine which is to be the general, which the sub-altern, for the rest of the campaign."