Today's market was sluggish.
彼は病気の後、しばらく不活発な生活を送っていた。
After his illness, he led an inactive life for a while.
不活発 describes being inactive or sluggish, the direct opposite of being 活動的.
Standard kanji spelling.
Variant using 溌 instead of 発; less common.
Compound of 不 (fu-, 'not') + 活発 (kappatsu, 'active, lively'). The kanji 活発 is a standard Sino-Japanese word meaning 'activity' or 'liveliness'.