knock something together
1. To collide. The first baseman and the pitcher knocked together and fell down, allowing the runner to reach first base.
2. To cause two things to come together or collide. A noun or pronoun can be used between "knock" and "together." We knocked our mugs together in a half-hearted toast.
3. To construct or produce something shoddily and hastily. A noun or pronoun can be used between "knock" and "together." With the way they just knocked together that bookcase, I'm not surprised it fell apart. Look at all these errors—I bet he just knocked this paper together before class.
knock something togetherand throw something together
tv. to assemble something—such as a meal—at the last moment. Bob knocked together some lemon chicken and rice in only a few minutes. I’ll see if I can throw something together.