Webster's Revised Unabridged Dictionary · 1913

Youngly

Youngly , adjective

[Anglo-Saxon geonglic.]

Like a young person or thing; young; youthful. [Obsolete] — Shakespeare

Youngly , adverb

1.
In a young manner; in the period of youth; early in life. [Obsolete] — Shakespeare
2.
Ignorantly; weakly. [Rare]