sure to happen at some time in the future.

If she wins next year's congressional race, it seems only a matter of time before she ends up running for the Senate.

Usage notes: usually used with only or just:

It's just a matter of time before prices for the newest computer come down.

• cock of the walk
• coffee table book
• cog in the machine
• cog in the wheel
• coin a phrase
• cold fish
• cold-shoulder
• cold-shoulder someone
• cold snap
• cold-turkey
• cold turkey
• Colonel Blimp
• come a cropper
• come across
• come across as
• come across someone
• come across something
• Come again?
• come again
• come a gutser
• come along
• come along for the ride
• come a long way
• come apart
• come apart at the seams