A general term that denotes the more efficient operation of a business. It covers eliminating wastage, cutting down costs, higher revenue per head, and many more. Many employees claim efficiency improvements but few measure their delivery. Real efficiency improvements can always be measured in cash - don't believe anyone who claims otherwise.
'Oh... I am far more efficient today than I was 10 years ago'... OK so prove it in real cash terms, because these are all that matter. For example, PC's and IT infrastructure have undoubtedly saved employee time, so have made people more efficient. There is a clear investment spend on equipment and clear time saved. Many claimed improvements are not valid in cash terms, unless the business itself rather than the individual gains the measurable benefits.