The upcoming 9.0 release of the SDK will switch all usages of the term OpMode to the form "OpMode". FTC Docs does not consistently use the form "OpMode", and should be updated to do so.
Additionally, the preferred way to refer to OpModes that specifically extend LinearOpMode (including Blocks OpModes) is "linear OpMode", and the preferred way to refer to OpModes that specifically extend OpMode directly is "iterative OpMode".