noun
leading shares; blue-chip stocks
Refers to stocks that are central to a market or portfolio, often of large, well-established companies. Common in financial contexts.
今日の東京市場では主力株が軒並み上昇した。
Leading shares rose across the board in the Tokyo market today.
彼のポートフォリオは主力株で構成されている。
His portfolio is composed of blue-chip stocks.
大型株 refers to large-cap stocks by market capitalization, whereas 主力株 highlights their leading role in the market.
Compound of 主力 (main force, leading) and 株 (stock, share). The term is a straightforward financial compound.