1. A failure to do something; esp., a neglect of duty (the complaint alleged that the driver had committed various negligent acts and omissions).
2. The act of leaving something out (the contractor’s omission of the sales price rendered the contract void).
3. The state of having been left out or of not having been done (his omission from the roster caused no harm).
4. Something that is left out, left undone, or otherwise neglected (the many omissions from the list were unintentional). — Formerly also termed omittance. — omit, vb. — omissive, omissible, adj.
