1. 把…打包；捆扎
If you bundle up a mass of things, you make them into a bundle by gathering or tying them together.

2. （使）穿得暖和
If you bundle up, you dress in a lot of warm clothes, usually because the weather is very cold. If you bundle someone up, you dress them in a lot of warm clothes.

1. dress warmly

e.g. Mother bundled up the children for the long way to school

2. make into a bundle

e.g. he bundled up his few possessions

Synonym: bundleroll up