What do you use to look up a word in dictionary?

As a large language model, I don't use physical dictionaries. I access and process information from the vast amount of text data I've been trained on.

However, if you want to look up a word in a dictionary, you can use:

* Online dictionaries: There are many free and paid online dictionaries like Merriam-Webster, Oxford Dictionaries, Dictionary.com, and Cambridge Dictionary.

* Dictionary apps: There are also dedicated dictionary apps for your phone or computer, like Merriam-Webster Dictionary, Oxford Dictionary of English, and Dictionary.com.

* Physical dictionaries: While less common now, you can still find physical dictionaries at libraries and bookstores.

The best method for you depends on your preference and the specific information you're looking for.