eggshell

Everyday

1. An eggshell is the hard thin outside cover of an egg, which breaks easily. tree →
2. Eggshell is a very pale off-white colour, like the inside of an egg's shell. tree →
3. Eggshell paint is paint with a soft, slightly shiny finish. tree →
4. «Walking on eggshells» means being very careful not to upset someone who gets angry or hurt easily. tree →

In the lessons

In science lessons eggshells are used to show that they are made of calcium carbonate, which fizzes in vinegar, and that a curved shell is surprisingly strong when pushed evenly. In cooking you must not get bits of eggshell in the cake mix; eggshells can go in the compost. The phrase «walking on eggshells» shows a tense feeling at home or in class. Phrases: crack the eggshell, bits of eggshell, eggshell white, walking on eggshells.

Examples

• She picked a bit of eggshell out of the pancake batter. tree →
• We put the eggshells in the compost bin. tree →
• The chick pecked its way out of the eggshell. tree →
• We soaked an egg in vinegar until the eggshell disappeared. tree →
• Mum painted the hall in eggshell white. tree →
• Everyone was walking on eggshells after the big argument. tree →
• An eggshell is mostly made of calcium. tree →
• You can grow cress seeds in an empty eggshell. tree →
• As soon as the water started to boil--tac!--he broke the eggshell. tree →

Note

Countable: one eggshell, many eggshells; also written as two words, «egg shell», but «eggshell» is more usual. Fun science fact: an eggshell is hard to crush when you squeeze it from both ends, because the dome shape spreads the push; it breaks easily on an edge. «Walking on eggshells» is an idiom, not about real eggs.