- kaolinized
- kapok oil
- katsura
- kauri
- keledang
- kemohalite
- kennel coal
- keranji
- kerosene distillate
- kerrite
- ketene
- Keuper stage
- key
- key board
- key rock
- keyaki
- kick off
- kilogram
- kim coal
- king bolt
- king pin
- kink band
- kipp generator
- kips
- kirving
- kit bag
- knee action
- knock inducer
- knock suppressor
- knockout
- knot
- kalnotype rock
- kaolinization
- kapok
- kar
- Karrer method
- karst lake
- karstenite
- karylnite
- Kazanian stage
- keel
- keeper plate
- kelat
- kelyphite rim
- kerargyrite
- kerosene coal
- keto form
- ketonic
- ketose
- kettle
- Kevlar
- Keyes process
- keyway
- kidney ore
- kies
- killing agent
- Kimeridgian stage
- kish
- kishy
- knacker line
- knap
- Kovar
- krablite
- kramerite
- kungurian stage
- kyanization
- labdanum oil
- labeled compound
- labeled molecule
- labile state
- lability
- laboratory reagent
- laboratory system
- laboratory work
- laburnum
- laccol
- laccolite
- lactate
- lacteal
- lactogenic hormone
- lacustrine environment
- ladder polymer
- ladder vein
- laden fluid
- Ladinian stage
- lag bolt
- lag gravel
- lagging
- lagoon
- lagoon moat
- lagoon shelf
- knife spreading
- knob
- knobby limestone
- knock rating
- knock test
- knocking tendency
- knockout vessel
- knoll
- knotenschiefer