adj

• (informal) Childish; immature.
  "So! here I find on kiddish mind / Traditionary lore instil'd. / Tho' fairly bookt, Nymph might have lookt / For poet's promise unfulfil'd."
• (informal) Of, like, or suitable for a child.
  "There was something kiddish about Clotilde, something especially kiddish as she strode along the winding country road, face uplifted, tinted with peach-blow color in either cheek, eyes bland and untroubled as an infant's, red lips parted over even white teeth, her whole slender body thrown, with a kind of kiddish abandon, into the business of getting ahead. "Boyish" she might have been called, not only for the clean-cut freshness of her face, but for the slimness of her hips, the unexaggerated curves of her uncorseted waist the flatness of her bosom on which the round little twin promontories were hardly noticeable when the wind threw her into momentary reliefs suggestive of the Winged Victory: "boyish" she might have been called if it be permitted to speak of a delicately-featured, prefect-complexioned, smooth-limbed boy as "girlish." Lacking this permission, the "boyish" must at once be withdrawn, and "finely girlish" substituted."

noun

• (rare) Alternative spelling of kiddush.
  "Each week, the kiddish was sponsored by a different member of the congregation. This being the Sabbath before Passover, the kiddish was sponsored by Max Warberg."