na-adjective
vague; dim; hazy; blurry; indistinct
Describes something that is not clear or distinct, such as memories, outlines, sounds, or understanding. Often used with 記憶, 輪郭, or 意識.
子供の頃の記憶はおぼろげだ。
My childhood memories are vague.
霧で山の輪郭がおぼろげに見える。
The outline of the mountain looks hazy in the fog.
The origin is uncertain; it may be related to おぼろ (hazy) with the suffix げ (appearing). The kanji 朧 (hazy) and 気 (spirit) are used for their meanings, but the word is usually written in kana.