Carl or Karl Hamilton may refer to:

• Carl B. Hamilton (born 1946), Swedish count, economist and politician
• Carl Hamilton (fictional character), fictional secret agent created by Jan Guillou
• Carl L. Hamilton (1888–1946), American businessman
• Karl Didrik Hamilton, on the list of governors of Örebro County
• Carl Hamilton (American football), New Mexico Lobos football coach
• Carl Hamilton (Governor) on List of governors of Östergötland County
• Carl Hamilton, candidate in the Ontario general election, 1977

• Diclidurus isabellus
• Diclidurus scutatus
• Dicliptera
• Dicliptera mucronifolia
• Dicliptera sericea
• Dicliptura
• Diclofen
• Diclofenamide
• Diclofenic
• Dicloflex
• Diclonius
• Diclonius (dinosaur)
• Diclonius pentagonus
• Dicloster
• Dicloxacillin
• Dicloxacillin sodium
• Dicmo
• DiCo
• Dicobalt octacarbonyl
• Dicoma
• Dicoma cana
• Dicomano
• Dicoma pretoriensis
• Dicomed
• Dicopatric speciation