- irrelevant cost
- irrelevant parameter
- irresoluble
- irresoluble equation
- irreversibility
- irreversible
- irreversible cycle
- irreversible cycles
- irreversible element
- irreversible encryption
- irreversible inhibitor
- irreversible line
- irreversible operation
- irreversible oxidation
- irreversible polarographic wave
- irreversible process
- irreversible reaction
- irreversible superconductor
- irreversible thermodynamics
- IRRI
- irrigation
- irrigation amount of each event
- irrigation and drainage experiment station
- irrigation and drainage history of China
- irrigation and drainage in China