yngje

• yngja (a-infinitive)
• ynga, ynge (without j-infix)

Derived from the adjective ung (“young”), with an i-umlaut probably introduced by analogy of other factitive verbs, such as how the verb tyngje (“to burden”) is derived from the adjective tung (“heavy”) (both present in Old Norse as þyngja and þungr respectively). Something similar appears to have happened in Icelandic yngja.

yngje (present tense yngjer, past tense yngde, past participle yngt, passive infinitive yngjast, present participle yngjande, imperative yng)

1. (transitive) to make younger
2. to have kids, kittens, etc.

• foryngje

• ung (“young”)
• yngjast (“to youngen”)

• “yngje” in The Nynorsk Dictionary.