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Tidal capture refers to independent bodies entering orbit when passing close, by slowing down relative to each other through tidal forces between them. It requires at least one non-ridged body such as a star, or planet which has a sizeable envelope. It is another means besides dynamic capture aka three-body capture, capture where gravity from a third body slows the relative motion of the two that enter into an orbit. Tidal capture may be a significant means by which binary stars are formed (i.e., tidal-capture binaries) within volumes that have a very high density of stars, such as the central regions of globular clusters.
Both tidal or dynamic capture require a happenstance of two bodies passing close, but dynamic capture is considered far more rare since it requires the coincidence of a third body passing close as well (though a third body orbiting one of the two can also serve). Likely more common is a swap, an interaction between a binary star and an additional star such that one of the binary companions ends up as a companion of the other star.