X
- Xanthic – yellowish
- xanthodont – one with yellow teeth
- Xenodocheionology – love of hotels
- xenogamy – cross-fertilization
- xenophilia – love of foreigners
- Xenophobia – fear of foreigners or strangers
- Xerotic – dryness as of eye or skin
- Xyloid woody
- Xylopolist – one who sells wood
- Xyster – surgical instrument for scraping bones