prop ‧ a ‧ gate /ˈprɒpəɡeɪt $ ˈprɑː-/ BrE AmE verb formal
[ Date: 1500-1600 ; Language: Latin ; Origin: past participle of propagare 'to breed plants from shoots' , from propago 'shoot from which a new plant is produced' ]
1 . [transitive] formal to spread an idea, belief etc to many people:
The group launched a website to propagate its ideas.
2 . [intransitive and transitive] if you propagate plants, or if they propagate, they start to grow from a parent plant to produce new plants:
Propagate your plants in fresh soil.
3 . [transitive] if an animal, insect etc propagates itself or is propagated, it increases in number SYN reproduce
—propagation /ˌprɒpəˈɡeɪʃ ə n $ ˌprɑː-/ noun [uncountable]