- IGFET
- IgG4-related disease
- IgG4 related kidney disease
- IgG4-related sclerosingcholangitis
- IgG4相关疾病
- IgG4相关硬化性胆管炎
- IgG4相关肾病
- IGHAT
- igh-order coherence
- IGM
- I. G. Macdonald
- I. G. Macdonald (1928—)
- IGMP
- Ignace Joseph Pleyel
- Ignacio de Loyola
- Ignacy Friedman
- Ignacy Jan Paderewski
- Ignacy Krasicki
- Ignatius Kögler
- Ignatiy Nikolaevich Potapenko
- Ignaz Günther
- Ignazio Silone
- Ignaz Moscheles
- Ignaz Philipp Semmelweis
- igneous facies