underdeveloped
adj. （国家或地区）不发达的，经济落后的；发育不全的；（胶卷）显影不足的
v. （使）发展不完全；（使）显影不足（underdevelop 的过去式和过去分词）
例句
His theory was inapplicable to many underdeveloped economies.
他的理论不适用于许多不发达的经济体。
《柯林斯英汉双解大词典》
Underdeveloped countries should be assisted by allowing them access to modern technology.
应该通过允许不发达国家使用现代技术来帮助它们。
Low average population densities are characteristics of most underdeveloped countries.
平均人口密度低是大多数不发达国家的特点。
