Haphazard means lacking any plan, order, or direction. When something happens in a haphazard way, it's random and disorganized, like throwing clothes into a suitcase without folding them or thinking about what you'll need.

If you study for a test in a haphazard manner, you might flip through your notes randomly instead of working through the material systematically. A haphazard pile of books on your desk has no organization: some are stacked, some are sideways, some are open. Compare this to a neat stack arranged by size or subject.

The word often suggests carelessness or lack of thought. A haphazard approach to building a treehouse might mean hammering boards wherever they seem to fit, which could result in a wobbly, unsafe structure. Scientists avoid haphazard methods because careful, systematic work produces reliable results.

You might hear someone say that books were arranged in a haphazard fashion on the shelf, or that a city grew in a haphazard way without urban planning.