Vakya literally means a sentence in Hinduism. It is a string of words arranged in certain juxtaposition and competent to express a meaning. Any string of words, however, does not make a vakya. For instance, a string of words such as ‘king milk donkey cat drink’ is not a vakya. For a vakya to be meaningful, it must fulfill four conditions, namely, akanksha, yogyata, asatti and tatparya.
Akanksha refers to the mutual expectancy of the constituent words of a sentence. Yogyata is concerned with the compatibility between words of a vakya. The sentence, ‘sprinkle with fire’ lacks yogyata, because the act of sprinkling is not compatible with fire. Asatti relates to the structural aspect of a vakya and means that in a vakya, there should be no unnecessary gaps or intervals between the words. Tatparya stands for the intended meaning of a sentence.
According to the Naiyayikas, vakyartha (sentence meaning) is simply the synthesis of the meaning of the constituent words of a vakya. The individual words have, in themselves, the meaning which can be comprehended separately. When we hear or read a vakya, we have first to understand the individual meanings of the constituent words of a vakya one after the other. Then by relating these individual word meanings on the basis of akanksha, yogyata, asatti, and tatparya, we arrive at the construed meaning of vakya. With the meaning of the last word of a vakya, together with the meanings of the preceding words by means of memory, we have an understanding of the meaning of the sentence as a whole. The cognition of the meaning of the sentence presupposes the cognition of the meaning of its constituent words. This theory is known as Abhihitanvayavada.