Synonyms for Cultivator (same or very similar meaning)
WordNet sense 1 (someone concerned with the science or art or business of cultivating the soil):
agriculturalist, agriculturist, grower, raiser
WordNet sense 2 (a farm implement used to break up the surface of the soil (for aeration and weed control and conservation of moisture)):
tiller
From the ODE community, based on WordNet
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