Splitfold

Splitfold is a term used across several domains to describe a process that combines a splitting action with a folding action. The exact meaning varies by context, and the term is often hyphenated as split-fold. It is not tied to a single canonical definition.

In mechanical engineering and automotive design, split-fold typically refers to a component or system that can fold along multiple lines, producing two or more sections that can be positioned independently. A common example is split-fold rear seats in passenger cars, which divide the seatback into sections (for instance 60/40) so that parts of the seat can be folded flat while the rest remains for passengers, allowing flexible cargo space.

In data processing and machine learning, the concept loosely corresponds to splitting a dataset into folds for cross-validation and then applying folding or aggregation to combine results. The phrase "split-fold" is not a standard term in the literature; practitioners usually refer to "split data for k-fold cross-validation" or "folded cross-validation."

In hashing and cryptographic contexts, some algorithms use a split-and-fold technique to mix input data, where input blocks are split and then folded into a smaller or larger state. These techniques are described with specific names and parameters rather than simply "splitfold."

See also: split, fold, split-fold rear seat, cross-validation, folding (hashing).