1. happening or chosen without a particular pattern, plan, or purpose
2. selected by chance from a group without bias
Usage: statistics; mathematics
3. strange or unexpected
Usage: informal

1. a random manner or state
Usage: usually in phrase ‘at random’

Examples

• The teacher called on students at random.
• We chose a random sample of 100 people for the survey.
• The computer generates random numbers for the lottery.
• That was such a random thing to say!
• She picked a book at random from the shelf.
• The results appeared to be completely random.
• Random events are difficult to predict.