Google search is not just a great search engine, but also a great library of utility functions. An example of this is the define: operator.
The define: operator acts as a dictionary: it lets you ask for the definition of a word. For example, searching for the below text gives me the definition of this strange word:
define:defenestration
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If you have a phrase you need to look up, feel free to throw it in as well. I wonder what this phrase means…
define:trip the light fantastic
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I often use this function to look up domain-specific words, such as words used only in the legal or technology fields, and I’ve always found useful, intelligent definitions.