Front and back

From an articulatory perspective, phonemes can be described as front or back.

This can either refer to vowels that are more front than central or, more rarely, only to fully front vowels, i.e. the ones articulated as far forward as possible in the mouth.

A back consonant features all consonants whose place of articulation is in the soft palate (velum) or further back, including velar, uvular, pharyngeal, and glottal consonants.

From the perspective of primary places of articulation, this includes all of the laryngeal consonants and some of the dorsal consonants (specifically, excluding palatal consonants).

This suggests that a three-way division between labial, acute and back (vaguely speaking, "P-like", "T-like" and "K-like", respectively) might be useful in some contexts.