proportional (n.)
- comparative
- connective
- contingent
- correlative
- dependent
- equal
- flat
- half
- half-and-half
- linking
- particular
- reciprocal
- relative
- space
- space-time
- surface
- sympathetic
proportional (adj.)
- analogical
- analogous
- associative
- balanced
- commensurable
- commensurate
- comparable
- comparative
- compatible
- congenial
- connective
- consistent
- contingent
- correlated
- correlative
- corresponding
- cubic
- dependent
- dimensional
- distributional
- distributive
- equal
- fifty-fifty
- flat
- half
- half-and-half
- harmonious
- linking
- particular
- pertinent
- proportionable
- proportionate
- proportioned
- reciprocal
- referable
- related
- relational
- relative
- respective
- several
- spatial
- spatiotemporal
- spherical
- stereoscopic
- superficial
- surface
- symmetrical
- sympathetic
- three-dimensional
- two-dimensional
- volumetric
