Perspective Distortion
The exaggeration of relative size between near and far objects when photographing from very close with a wide lens.
In depth
Like compression, this is a function of distance rather than focal length — the wide lens merely allows the close position. Because a nose is proportionally much nearer the lens than the ears, close portraits with wide lenses enlarge central features, which is the real reason 85 to 135 mm became the classic portrait range.
Examples in practice
A face photographed at 30 cm with a 24 mm lens shows an enlarged nose and diminished ears.