na-adjective
half-done; mediocre; half-hearted
Describes something done without full commitment, skill, or thoroughness; often used with a negative connotation. Similar to 中途半端 (ちゅうとはんぱ).
生半な気持ちでは成功できない。
You can't succeed with a half-hearted attitude.
彼の知識は生半だ。
His knowledge is superficial.
adverb
half-heartedly; insufficiently
Adverbial use; often appears as 生半に or 生半な. Indicates doing something without enough effort or thoroughness.
See also: なまじっか
生半に勉強しても試験に受からない。
If you study half-heartedly, you won't pass the exam.
Compound of 生 (なま, 'raw, half-') and 半 (なか, 'half'). The exact historical derivation is uncertain, but the combination reinforces the idea of incompleteness.