|1.||Cranking a semi|
Having half an erection at the thought of something quite arousing. Not quite full blown but at the same time not quite a flopster.
Other words can be used in replacing cranking, including:
The girl walked by and the boy smiled, only when she looked at him with disgust did he realise he had been cranking a semi.
Ted studdied the Bellaby Continuum with pleasure before realising he was cranking a semi.