1. Gentle utterance use to call someone's attention
   - ahem, hem 
2. Exclamation expressing doubt, deliberation, dissent, or hesitation
   - hum, ahem

Encyclopedia: Hmm

• item
• item-by-item
• itemisation
• itemise
• itemization
• itemize
• iter
• iterant
• iterate
• iteration
• iterative
• iterative aspect
• iteratively
• Ithaca
• Ithaki
• Ithiel Town
• Ithunn
• ithyphallic
• itineracy
• itinerancy
• itinerant
• itinerary
• itinerate
• itineration
• itraconazole