• 機械きかい — machine
• 機会きかい — opportunity
• 飛行機ひこうき — airplane
• 危機きき — crisis
• 機能きのう — function
• 新機種しんきしゅ — new model (machine)
• 機関きかん — engine / institution

木 (きへん, “wood”) points to the original wooden loom, while 幾 provides sound and nuance of intricacy. Together, 機 meant “loom,” later expanding to “machine,” “mechanism,” and abstractly “opportunity.”