接地

Two registers. Technical: literal electrical earthing — 接地线 'ground wire', 接地电阻 'ground resistance'. Colloquial: 接地气 (jiē dìqì, 'connect to earth-energy') = 'down-to-earth, in touch with ordinary people' — a hugely popular compliment for politicians, celebrities or products that don't feel elitist.

memory

Same metaphor as English 'grounded' — both languages independently picked the electrical 'earth connection' to describe a person who hasn't lost touch with reality.