12-letter words containing u, n, f, m
- unperforming — not performing
- unreformable — not able to be reformed or reclaimed
- unremorseful — full of remorse.
- unsimplified — to make less complex or complicated; make plainer or easier: to simplify a problem.
- wing formula — a numerical representation of the relative lengths of the primary feathers of a bird's wing, used in identifying similar species, as flycatchers.