Not formed or made. / Not having a definite form; shapeless; amorphous. / Not well developed. / Decomposed, or resolved into parts; having the form destroyed.

That has not been formalized.

Unable to be formed.

Third-person singular simple present indicative form of unform

To destroy the form of; to decompose, or resolve into parts; to unmake.

present participle of unform

(rare) The reverse of formation; taking or coming apart; disassembly.

Not formal.

Not formative.

informally