A person who is incompetent.
Not resistant to deformation or flow.
Unable to make rational decisions; insane or otherwise cognitively impaired.
Opening too early during pregnancy, resulting in miscarriage or premature birth.
Unskilled; lacking the degree of ability that would normally be expected.
something that causes privation or indicates an absence
causing privation; depriving
consisting in the absence of something; negative
indicating the absence of something