paulcna fu'ivla

x1 [signed quantity] is the the intrinsic spin/signed spin quantum number/magnetic quantum number/Dirac-Pauli spin-like charge [commonly denoted: s] of particle/thing x2, as measured along axis/in direction/measuring component x3

Contextless default for x3 is probably along the z-axis in the positive direction or any axis at all. For an electron, this quantity has absolute value of hbar/2 [the Lojban ignores the technical issue in English of "spin" versus "spin quantum number"]. Pay attention to the fact that plankexu is defined as equalling hbar/2, not just hbar. See also: plankexu.

In notes:

x1 (object) has charge x2 (number) in units x3 for interaction/of type x4 and in/by/using convention x5
x1 is the elementary unit (quantum) of angular momentum/half of Planck's reduced constant [id est: hbar/2 = h/(4 pi)] expressed in units x2 (default: unitless/dimensionless and so that it is equal to 1) in paradigm/system/metaphysics/universe x3 (default: this, our actual, physical universe)