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

To make voiceless

• thromboses
• thrombosing
• thrombosis
• thrombotic
• thrombus
• throne
• throned
• throneless
• throne room
• throne rooms
• thrones
• throng
• thronged
• throngful
• thronging
• throngings
• throngs
• throning
• thropple
• throppled
• thropples
• throppling
• throstle
• throstle-cock
• throstle-cocks