knock on wood
used to say that you hope your good luck so far will not change SYN touch wood

[TahlilGaran] Dictionary of Contemporary English ▲

knock on wood
knock (on) wood
I hope my good luck will continue.
We haven't had any problems with the car so far, knock on wood.

I'm expecting, knock wood, to be offered the job next week.

Usage notes: used when you think difficulties are likely
Etymology: possibly from the idea of knocking on a tree to ask the magical creatures inside for help

[TahlilGaran] English Idioms Dictionary ▲

knock on wood
knock on something made of wood to keep from having bad luck
I don't think that I will lose my job - knock on wood.

[TahlilGaran] English Idioms Dictionary ▲

knock on wood
v. phr. To knock on something made of wood to keep from having bad luck.
■ Many people believe that you will have bad luck if you talk about good luck or brag about something, unless you knock on wood; often used in a joking way.
Charles said, "I haven't been sick all winter." Grandfather said, "You'd better knock on wood when you say that."

[TahlilGaran] English Idioms Dictionary ▲