Read along with the three podcasts, or open the full dictionary entry for Cesium for the definition, Arabic meaning, synonyms and example sentences.
Narrator: Today's word is "Cesium" — noun, pronounced /ˈsiːziəm/, with the stress on "see".
Narrator: Cesium, spelled caesium in British English, is a soft, gold-coloured alkali metal with atomic number 55.
Narrator: In plain English, cesium is the metal that keeps the world's most accurate clocks.
Narrator: It comes from the Latin caesius, sky blue, for the blue lines in its spectrum.
Narrator: "A cesium atomic clock" describes the clocks that define the second.
Narrator: It differs from sodium because cesium is far more reactive and explodes in water.
Narrator: "Cesium-137" is a second pattern, a radioactive isotope from nuclear accidents.
Narrator: Timekeeping, satellite navigation, drilling and medicine all rely on cesium.
Narrator: So remember: cesium is the reactive metal that defines the second.
Speaker A: What is cesium?
Speaker B: A clock-keeping metal! CESIUM comes from the Latin caesius, sky blue.
Speaker A: Is it really the definition of a second?
Speaker B: Yes — the second is defined by cesium atom vibrations!
Speaker A: Example sentences?
Speaker B: "GPS relies on cesium clocks"; "Cesium explodes in water"; "Cesium-137 spread after Chernobyl" — navigation, lab and history.
Speaker A: Common mistakes?
Speaker B: Don't forget the British spelling caesium, because British texts usually write it with ae.
Speaker A: Close relatives?
Speaker B: 'Rubidium' the lighter cousin, 'francium' the rarer twin, 'potassium' the common alternative. The word keeps its tick-tock charm!
Speaker B: Let's use "Cesium" in AI prompts — useful for time services and science apps.
Speaker A: So a prompt could frame time?
Speaker B: Right. For a time app, you'd write:
Prompt: Explain how a cesium atomic clock keeps time for GPS satellites.
Speaker A: How about spelling?
Speaker B: Ask the model to handle:
Prompt: Make the search box accept both cesium and caesium and show the same result.
Speaker A: Could it help with safety?
Speaker B: Yes, you can frame summaries:
Prompt: Summarise the health risks of cesium-137 after a nuclear accident in plain English.
Speaker A: One more?
Speaker B: For a demo, try this:
Prompt: Write a short script for a video showing how alkali metals react more strongly down the group.
Cesium — meaning in Arabic & definition More C courses GL Dictionary