Glass, Hinged Structure for Protecting Seedlings
Puzzle 4 of Yoga Hard Pack
Question is: Glass, Hinged Structure for Protecting Seedlings
and the answer is: COLDFRAME
Word Meaning:
COLD FRAME — (agriculture, horticulture) A transparent-roofed enclosure, built low to the ground, used to protect plants from cold weather.
Definitions from Wiktionary.