x_{1} is a pure real number (such that its imaginary part is 0) understood as an example of a complex number.

Includes 0 = (0,0) = 0 + 0i. This word relies on xo'ei implicitly filling the second slot of "ka'o" and also relies on the Cartesian decomposition of all complex numbers into real and imaginary bases (due to ka'o). It is important to note that this is isomorphic to a 'normal' real number but is not one; it is a complex number with imaginary part 0. See also: ka'o zei namcu and nozeika'o zei namcu.

- namcu
- x
_{1}(li) is a number/quantifier/digit/value/figure (noun); refers to the value and not the symbol. - zekri
- x
_{1}(event/state) is a punishable crime/[taboo/sin] to people/culture/judges/jury x_{2}.

- cmapagjvo
- x
_{1}(text) is a lujvo with meaning x_{2}and arguments x_{3}, and which is constructed from tanru/veljvo x_{4}such that each element of the veljvo is ultimately only a cmavo (including "{zei}", "{ke}"/"{ke'e}", "{bo}", etc.), gismu, or rafsi of such cmavo or gismu. - zejvo
- x
_{1}(text) is a Lojban compound predicate using the particle “zei”; with meaning x_{2}, arguments x_{3}, built from metaphor (tanru) x_{4}. - luvrzei
- x
_{1}(text) is a Lojban compound predicate using the particle “zei”; with meaning x_{2}, arguments x_{3}, built from metaphor (tanru) x_{4}. - zeiljvo
- x
_{1}(text) is a Lojban compound predicate using the particle “zei”; with meaning x_{2}, arguments x_{3}, built from metaphor (tanru) x_{4}. - zo si si zei fa'o
- x
_{1}is a nonsense zei-lujvo using parts x_{2}, silly by standard x_{3}.

- ka'o zei namcu
- x
_{1}is a complex number (understood as such). - nozeika'o zei namcu
- x
_{1}is a pure imaginary number (such that its real part is 0) understood as an example of a complex number.