The sentence-meaning? What is added over the word-meaning

One can understand what is the sentence-meaning if one compares it with the meaning of the word-meanings composing the sentence. Is it their sheer sum? Something completely different? Jayanta proposes that it is the additional element over the meanings of the words taken singularly.
Jayanta Bhaṭṭa's Nyāyamañjarī, 5:

Nor is it the case that there is no sentence-meaning separated from word-meanings. That, to begin with, you (the PP) should explain, if you are asked to: "Is there a cognition similar to the word cow, etc., arising from "Bring the white cow!" or are the two cognitions different? In this regard, we should start by saying (tāvat) the sameness of the two runs against direct experience. In the case of a difference of the two cognitions, by contrast, also a difference in their contents is forcibly (balāt) produced (upanata), since if there were no difference in content one would not grasp a difference in the cognitions. And that content which is separated from them (content of the words) is the sentence-meaning. In this way, it should be construed also in case only a word signifying a quality or an action has been pronounced (i.e., even in the case of sentences made of one word only, there is something additional over the sheer meaning of the word).
Therefore it has been said that the sentence-meaning is that in which there is something additional.

(na ca padārthavyatirikto nāsti vākyārthaḥ | idaṃ tāvad bhavān pṛṣṭo vyācaṣṭāṃ | kiṃ gaur iti padādyādṛśī pratipattis tādṛśyeva gauḥ śukla ānīyatām iti vākyād uta bhinne ete pratipattī iti |
tatra tulyatvaṃ tāvat pratipattyor anubhavaviruddham | vailakṣaṇye tu pratītyor viṣayavailoakṣaṇyam api balād upanatam asati viṣayabhede pratītibhedānupapatteḥ | taś ca tad atirikto viṣayḥ sa vākyārthaḥ | evaṃ kevalaguṇakriyāpadoccāraṇe ’pi yojanīyam | tad uktaṃ yatrādhikyaṃ sa vākyārtha iti | )

For further references to posts dedicated to Jayanta and to his linguistic theories, see here.