诸子百家

Umbrella term for the philosophical explosion of the late Zhou — 诸子 ('the various masters': Confucius, Mencius, Laozi, Zhuangzi, Mozi, Han Feizi, etc.) and 百家 ('the hundred schools': Confucian 儒, Daoist 道, Mohist 墨, Legalist 法, School of Names 名, Yin-Yang 阴阳, and many more). Han historian Sima Tan grouped them into six schools; later 班固 expanded the count to ten.

Literally 'all the masters, hundred schools' — 诸 = various, 子 = master/philosopher (as in 孔子, 老子), 百 = hundred (figurative for 'many'), 家 = school of thought. The same 家 appears in 法家 (Legalists), 儒家 (Confucians), 道家 (Daoists).