By Mary Morel
Dis- as a prefix often implies the reversing of the action of the verb (e.g. disagree, disown, distrust).
Un- as a prefix means ‘not’ (e.g. unable, unusual, untidy).
Disorganised and unorganised are often used interchangeably to mean not arranged in an orderly way.
His desk is disorganised.
His desk is unorganised.
But they have subtly different meanings.
Disorganised has a sense of confusion or disorder. Unorganised is more neutral.
His desk is unorganised, but he knows where everything is.
His desk is disorganised and he can’t find a thing.
You can’t rely on a disorganised person to get things done.
She appears unorganised but everything is under control.
I don’t use unorganised much. Other words often seem more appropriate.
Her desk is a mess, but she knows where everything is.
Her desk is not well organised, but she knows where everything is