omission
n. 1) failure to perform an act agreed to, where there is a duty to an individual or the public to act (including omitting to take care) or where it is required by law. Such an omission may give rise to a lawsuit in the same way as a negligent or improper act. 2) inadvertently leaving out a word, phrase or other language from a contract, deed, judgment or other document. If the parties agree that the omission was due to a mutual mistake, the document may be "reformed," but this may require a petition for a court order making the correction if it had been relied upon by government authorities or third parties.