acti - air
- acting
- actinic
- actinic effect
- actinic screen
- actinides
- actinism
- actinium
- action
- action turbine
- action variable
- activate
- activated
- activating agent
- activation
- activator
- active
- active account
- active carbon
- active component
- active component of the voltage
- active cooling surface
- active current
- active energy meter
- active lattice ( of a reactor)
- active lime
- active power
- active product
- active volcano
- activity
- actual
- actual address
- actual current
- actual efficiency
- actual error
- actual gas
- actual horsepower
- actual load
- actual output
- actual range
- actual reserves
