grass

Concise Oxford English Dictionary © 2008 Oxford University Press:
grass/ɡrɑːs/

▶noun

• 1 vegetation consisting of short plants with long narrow leaves, growing wild or cultivated on lawns and pasture.

  ■ ground covered with grass.

• 2 a plant with jointed stems and spikes of small wind-pollinated flowers, predominant in such vegetation. [Family Gramineae: many species.]

• 3 informal cannabis.

• 4 Brit. informal a police informer.

▶verb

• 1 cover with grass.

• 2 (often grass on) Brit. informal inform the police of criminal activity or plans.

• 3 land (a fish).

• 4 chiefly Rugby & Australian Rules knock down.

– phrases
at grass grazing.
not let the grass grow under one's feet not delay in taking action.
put out to grass put (an animal) out to graze.

■ informal force (someone) to retire.

– derivatives
grassless adjective,
grass-like adjective.

– origin OE græs, of Gmc origin; ult. rel. to green and grow. The sense ‘police informer’ is perh. rel. to C19 rhyming sl. grasshopper ‘copper’.