Underexpanding

Part of speech: verb, adjective

Definitions

1. Failing to expand enough or adequately, such as when something grows or increases less than expected
2. Displaying insufficient growth or extension beyond the usual or intended amount
3. Showing a lack of proper enlargement or increase, resulting in less than the desired expansion

Etymology: "Expand" comes from Latin "expandere," built from "ex-" meaning "out" and "pandere," meaning "to spread." So at its root, to expand is to spread something outward, and the Latin verb is the source of the English word. "Under-" is an older English prefix, and here it means "insufficiently" or "not enough." Attached to "expanding," it gives the sense of growing or spreading too little. The same pattern produces "underestimating" and "underdeveloped," and it can serve as either a verb form or an adjective, as this word does.