tufa /tooˈfə, tūˈfə/

1. Calc-sinter (often calcareous tufa)
2. Tuff or other porous rock (obsolete)

tufāˈceous adjective

• keyhole saws
• keyhole surgery
• key in
• key industries
• key industry
• keying
• keyless
• key light
• key lights
• keyline
• keylines
• keylogging
• key man
• key men
• key money
• Keynesian
• Keynesianism
• keynote
• keynoted
• keynotes
• keynoting
• keypad
• keypads
• keypal
• keypals