noun which may take the genitive case particle 'no'
untrained; uneducated; lacking training
Describes a person or animal that has not received proper training or education. Often used in contexts like 未教育の犬 (untrained dog) or 未教育な社員 (untrained employee).
未教育の犬は、散歩中に他の犬に吠えることがある。
An untrained dog may bark at other dogs during walks.
未教育な新人には、まず基本的なマナーを教える必要がある。
For untrained newcomers, you first need to teach them basic manners.
未熟 means 'immature' or 'unskilled' and is more about lack of experience or skill, whereas 未教育 specifically refers to lack of training or education.
Compound of 未 (mi, 'not yet') + 教育 (kyōiku, 'education'). The prefix 未- attaches to nouns to indicate something has not yet occurred or been done.