1. In a meaningless and purposeless manner
   "these innocent bystanders were senselessly killed" 
2. In an unreasonably senseless manner
   - mindlessly

See also: senseless

• antique
• antiquity
• antiredeposition
• Antirrhinum
• Antirrhinum coulterianum
• Antirrhinum filipes
• Antirrhinum majus
• antisatellite
• antiscorbutic
• antisemitic
• antisemitism
• antisepsis
• antiseptic
• antiseptically
• antisepticise
• antisepticize
• antiserum
• antislavery
• antisocial
• antisocial personality disorder
• antisocially
• antispasmodic
• antispasmodic agent
• antistatic mat
• antistrophe