devocalize or devocalise /dē-vōˈkə-līz/ or devoice /dē-voisˈ/

To make voiceless

• chuff-chuff
• chuff-chuffed
• chuff-chuffing
• chuff-chuffs
• chuffed
• chuffier
• chuffiest
• chuffiness
• chuffinesses
• chuffing
• chuffs
• chuffy
• chug
• chugged
• chugger
• chuggers
• chugging
• chugs
• chukar
• chukars
• chukka
• chukka boot
• chukka boots
• chukkas
• chukker