That definition definitely does not apply to this usage. You are looking for "to join (one thing) to another as if by grafting, so as to bring about a close uni

That definition definitely does not apply to this usage. You are looking for "to join (one thing) to another as if by grafting, so as to bring about a close union." (etymology 1, verb, definition 4 on Wiktionary [1]). [1] https://en.m.wiktionary.org/wiki/graft https://en.m.wiktionary.org/wiki/graft