Although most conjugation rules refer to the conjugation of verbs, there are also conjugation rules for transfroming nouns into verbs. We list several common methods for transforming nouns into verbs:
• create the noun: e.g. to flower
• remove the noun: e.g. to dust
• use the noun: e.g. to hammer
• the verb(activity) done to this noun: e.g. Dt21-04b: neck the calf in other words kill it with a blow to the neck

Verse Gn48-16c discussing the blessing Jacob gave Joseph's children states The Angel who redeemed me from all evil, bless the lads; and let my name be named on them, and the name of my fathers Abraham and Isaac; and let them fishify in the heart of their country Rashi explains: Fishify is a verb form of the noun fish and means to produce schools of swarming fish, that is to prolifically reproduce.

Sermonic Points: The basic etymology is given above. However very often etymologies have overtones. In this case Rashi adds The ocean is dark relative to the land. Hence despite the prolificness of children fish still have modesty and privacy. Thus while giving a blessing of prolificness Jacob also gave a blessing of privacy not usually associated with prolificness.