edge

Everyday

1. An edge is the outside line or end of something, like the edge of a table or a cliff. tree →
2. An edge of a solid shape is the line where two faces meet. A cube has 12 edges. tree →
3. The edge of a knife is its sharp side. tree →
4. To edge is to move slowly and carefully. tree →
5. «On edge» means nervous. tree →

In the lessons

maths: edges of shapes counted (a cube has 12, a triangular prism 9), or the border around something, as in perimeter; along an edge means the length around; science: the edge of a forest or pond, where habitats meet; everyday life and safety: stay away from the edge of the platform, cliffs and pools; stories: on the edge of a cliff

Examples

• A cube has 12 edges. tree →
• She put a ribbon along the edge of the table. tree →
• How many edges does a triangle prism have? tree →
• Plant a tree every 2 meters along the edge. tree →
• Stand back from the edge of the platform. tree →
• The knife has a sharp edge. tree →
• He edged along the narrow wall. tree →
• The cat sat on the edge of the bed. tree →
• The Goat looked over the edge of the cliff. tree →

Note

Fixed numbers for solids; along an edge means the length around (perimeter). Trap: a cube has 12 edges but 8 corners and 6 faces. Trees along an open edge need one more than the gaps.

In Jewish tradition

Interpretation: "The edge of the sword" is a Torah phrase for the sword's cutting side, used of battle, as when Joshua defeated Amalek. In the primary lessons: maths: edges of shapes counted (a cube has 12, a triangular prism 9), or the border around something, as in perimeter; along an edge means the length around; science: the edge of a forest or pond, where habitats meet; everyday life and safety: stay away from the edge of the platform, cliffs and pools; stories: on the edge of a cliff

Examples

• And Joshua discomfited Amalek and his people with the edge of the sword. (Torah EXO.17.13, JPS 1917) tree →
• And they took their journey from Succoth, and encamped in Etham, in the edge of the wilderness. (Torah EXO.13.20, JPS 1917) tree →
• And they journeyed from Succoth, and pitched in Etham, which is in the edge of the wilderness. (Torah NUM.33.6, JPS 1917) tree →
• But her end is bitter as wormwood, sharp as a two-edged sword. (Writings PRO.5.4, JPS 1917) tree →
• Let the high praises of God be in their mouth, and a two-edged sword in their hand; (Writings PSA.149.6, JPS 1917) tree →
• Yea, Thou turnest back the edge of his sword, and hast not made him to stand in the battle. (Writings PSA.89.44, JPS 1917) tree →

Note

Fixed numbers for solids; along an edge means the length around (perimeter). Trap: a cube has 12 edges but 8 corners and 6 faces. Trees along an open edge need one more than the gaps.