绑 means to tie or bind with rope or string. Common compounds: 绑架 (bǎngjià, to kidnap), 绑定 (bǎngdìng, to link/bind an account), 捆绑 (kǔnbǎng, to bundle/tie up).
Left silk-radical 纟 (contracted form of 糸) — the indexing radical. Anchors 绑 in the family of cord-and-binding verbs: 系 (tie), 缠 (wind), 缚 (bind). The thread is what does the tying.
Right 邦 supplies the sound (bāng → bǎng, just a tone shift). 邦 originally meant a fortified territory — semantically distant, so it functions purely as a phonetic loan. Same phonetic family: 帮 bāng (help), 梆 bāng (clapper).
