sound the death knell for (something)

to cause something to end.

Everyone likes e-mail, but it hasn't sounded the death knell for snail mail quite yet.

Etymology: based on the literal meaning of sound the death knell (= to ring a church bell slowly to announce a person's death)

• straight up
• strain every nerve
• strangely enough
• straw in the wind
• straw that breaks the camel's back
• street smarts
• stretch legs
• stretch the rules
• keep a weather eye on something
• keep body and soul together
• keep both feet on the ground
• keep cards close to chest
• keep cards close to your chest
• keep chin up
• keep close watch on
• keep close watch on someone
• keep close watch on something
• keep company
• keep company with
• keep company with someone
• keep cool
• keep dark
• keep distance
• keep distance from
• keep distance from someone