The study of meaning in a language is known as—

The correct answer is semantics.

In linguistics, semantics is the subfield devoted to the study of meaning in language, including the meaning of words, phrases, signs, and symbols.

Let's briefly look at the other options to understand why they are incorrect:

• Syntax: The study of sentence structure and the rules governing how words combine to form phrases and sentences.
• Morphology: The study of the internal structure of words and how morphemes (the smallest units of meaning) combine to form words.
• Linguistics: The overall scientific study of human language and its structure as a whole.