1) Early progress 2) Fragile footing 3) Initial access 4) Initial advantage 5) Initial bit of progress 6) Initial gain 7) Initial progress 8) Insecure grip 9) Merest grip 10) Position 11) Slight footing 12) Slight or initial advantage 13) Slight support 14) Small initial advantage 15) Small purchase 1) Grip 2) Perch 
a saw kerf or other means (hardware cloth, rough wood) that allows nestlings to grab onto the nestbox wall to fledge.
[n] - a small foothold used in climbing 2. [n] - a wrestling hold in which the toe is held and the leg is twisted against the joints
noun a wrestling hold in which the toe is held and the leg is twisted against the joints