This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 彠 is uncertain. It appears to combine 尋 and 蒦, but the original semantic and phonetic roles are unclear.
Since the meaning is unclear, focus on the shape: 尋 on the left suggests searching or measuring, and 蒦 on the right is a complex component seen in other characters. Together they form a dense, rare kanji.
For ワク, imagine a rare measuring tool called a 'waku' that looks like the complex shape of 彠: waku -> ワク.