On grammatical class:

mo'e
convert sumti to mex operand; sample use in story arithmetic: [3 apples] + [3 apples] = what.

In definition:

cmavrmo'e
x1 is the selma'o "MOhE".

In notes:

ci zei mektika
x1 is a part of Lojban text representing rule 'operand-3' according to the first edition of the book 'The Complete Lojban Language'.