periodic

Everyday

1. Periodic means happening again and again, at regular times or now and then. tree →
2. (science) The periodic table is the chart of all the chemical elements in order. tree →

In the lessons

In science lessons the periodic table lists elements like hydrogen, oxygen and gold. In maths a periodic pattern repeats, like the days of the week or a repeating decimal. In everyday life: periodic checks, periodic visits. Phrases: «periodic table», «periodic checks».

Examples

• The periodic table has more than a hundred elements. tree →
• We do periodic fire drills at school. tree →
• The doctor gives the baby periodic check-ups. tree →
• The tide is periodic: it comes in and goes out. tree →
• There were periodic showers all day. tree →
• The pattern 1, 2, 1, 2 is periodic. tree →
• The car needs periodic servicing. tree →
• Find gold on the periodic table. tree →

Note

Stress: peer-ee-OD-ic. Adverb: periodically. In maths a periodic pattern repeats after a fixed number of steps; to find the 20th term, use the repeat length (remainder after division).