babyhead
n.— «The group trudges onward, scrambling over teetering scree—rocks first the size of oranges and then as big as volleyballs (called “babyheads” in climbing lingo).» —“Former Texas lawmaker heads for the hills in quest to climb Colorado’s highest peaks” by Pamela LeBlanc in Twin Lakes, Colorado Austin American-Statesman (Texas) Aug. 5, 2007. (source: Double-Tongued Dictionary)