adjective
- unintentional: an inadvertent insult.
- not attentive; heedless.
- of, relating to, or characterized by lack of attention.
adjective
- failing to act carefully or considerately; inattentive
- resulting from heedless action; unintentional
1670s, literally “inattentively,” hence “unintentionally;” see inadvertent + -ly (2).
1650s, back-formation from inadvertence.