Did the Buddha invent any words?

At large, the Sublime Buddha used existing perceptions, words, and gave them deeper meaning, meaning, perceptions which lead to longer happines and beyond. "Put things upright, which had been overthrow.." Sure, there might be conjunctions before not used that way. But as english is rather void of using conjunctions and usually inflexible used, it's difficult to draw a simile here. Now the answer requires to trust that one understands the meaning of perception/remembering.

Another point in the teachings of the Buddha is a remarkable, often misunderstood: sequences of words with similar meaning, to simply match others perception clear. Many think that certain list carry different, seeking for seperate different, but actually it has simple such purpose, as well as using different words for same, same. Perceptions are different for each person. How one perceives (remembers), so does one think. Way to the understanding of Dhamma means to train oneself in useful perceptions, remember right, turn attention toward what is worth of attention.

Yet, what if not getting this point here 'baken' would have made any use of a question whether the Buddha was a word-inventor or not?

According to Bhante Vimalaramsi, "samadhi" was coined by the Buddha.

Now, the last factor--I've got a lot to say about that one--"Right Concentration." One of the observations that Rhys Davies made about the word "concentration" (or "samadhi" in Pali) was that that word was never used in the time of the Buddha. The Buddha made this word up to describe a particular kind of mental development. But Rhys Davies, because of his ignorance, called it "concentration," and it's been called "concentration" ever since. And any time anybody thinks about "concentration," they think about one-pointedness of mind. Because there were a lot of practices that were being practiced during the time of the Buddha, a lot of different kinds of meditation, and they were all one-pointed concentration. The Buddha could have picked up one of those other Pali words that meant one-pointed concentration, but he didn't. He made up a word to describe something different. So my definition of "samadhi" is "collectedness." Collectedness has stillness, calm, and composure.

This is at the beginning of VIII. Harmonious Collectedness

The Buddha invented his own terms and defined them, using everyday words that already existed in the local dialects.

First, discussion on the language he used, is found in "The Authenticity of the Early Buddhist Texts" by Bhikkhu Sujato and Bhikkhu Brahmali below. Pali is a constructed language that is closely related to the Buddha's original dialect (Magadhan Prakrit).

Early generations of Indologists accepted the traditional Theravādin claim that Pali was the language of the Buddha. More recent linguistic studies,however, show that Pali is in part an artificial language, created some time after the Buddha [3, 140]. However, the differences in language between Pali and the historically datable language of the Asokan pillars are no more than minor phonetic changes that rarely, if ever, affect the meaning of the content. In all probability a similarly close relationship obtains between Pali and the historical Buddha’s own dialect [2, 194] [9, 11].

Moreover, the Buddha himself may have used varying dialects depending on where he travelled [2, 190–191] [5, 99], and certainly his disciples did: they were in fact encouraged to speak in their own dialect. As Buddhism spread throughout Northern India, this diverging use of language must eventually have led to a need for standardisation, and this probably explains the introduction and development of Pali. Alternatively, or perhaps complementarily, Pali is related to a particular dialect in India from where the missions to Sri Lanka originated. A number of scholars are of the opinion that the West-Indian dialect associated with the Asokan rockedicts at Girnār and Bombay-Sopārā are closely related to Pali [7, 73–74][9, 8–9]. The precise age of Pali, therefore, does not have any bearing onthe age of the contents of the EBTs.

Finally, there are no certain traces of Sinhalese influence on the Pali EBTs [4, 246] [5, 102–103]. This suggests that the EBTs were in a standardised form when they arrived in Sri Lanka around the time of Asoka and that they are unlikely to have been changed after this. As Wynne says: “If the language of the Pali canon is north Indian in origin, and without substantial Sinhalese additions, it is likely that the canon was composed somewhere in north India before its introduction to Sri Lanka, and is therefore a source for the period of Buddhism in Northern India before this” 2, that is,before Asoka. In contrast, Pali texts actually composed in Sri Lanka do show influence from both Sinhalese and Dravidian [6, 6]

According to Bhikkhu Bodhi (from here):

Scholars regard this language (Pali) as a hybrid showing features of several Prakrit dialects used around the third century BCE, subjected to a partial process of Sanskritization. While the language is not identical to what Buddha himself would have spoken, it belongs to the same broad language family as those he might have used and originates from the same conceptual matrix. This language thus reflects the thought-world that the Buddha inherited from the wider Indian culture into which he was born, so that its words capture the subtle nuances of that thought-world.

Secondly, the Buddha forbade his disciples from using Sanskrit, the language of the royal court and of the Brahman clergy. Instead he wanted his disciples to use the local dialects of the common people. This can be found here, in the Theravada Vinaya, in Cullavagga, fifth Khandaka, chapter 33:

And so sitting those Bhikkhus spake to the Blessed One thus:

'At the present time, Lord, Bhikkhus, differing in name, differing in lineage, differing in birth, differing in family, have gone forth (from the world). These corrupt the word of the Buddhas by (repeating it in) their own dialect. Let us, Lord, put the word of the Buddhas into (Sanskrit) verse.'

'How can you, O foolish ones, speak thus, saying, "Let us, Lord, put the word of the Buddhas into verse?" This will not conduce, O foolish ones, either to the conversion of the unconverted, or to the increase of the converted; but rather to those who have not been converted being not converted, and to the turning back of those who have been converted.'

And when the Blessed One had rebuked those Bhikkhus, and had delivered a religious discourse, he addressed the Bhikkhus, and said:

'You are not, O Bhikkhus, to put the word of the Buddhas into (Sanskrit) verse. Whosoever does so, shall be guilty of a dukkata. I allow you, O Bhikkhus, to learn the word of the Buddhas each in his own dialect.'

Thirdly, the Buddha redefined words from ordinary language into technical terms with specific meaning, depending on context.

For e.g. "dhamma" could mean "phenomena" or "thing", "concept", "teachings" depending on context.

And "sankhara" also means different things depending on context, as seen in this question.

The five aggregates (rupa, vedana, sanna, sankhara, vinnana) are defined in SN 22.79.

The world or "loka" is discussed in this question.

The All or "sabba" is discussed in this question.

Heedfulness or "appamada" is discussed in this question.

Noble or "ariya" is discussed in this question.

Another one is "ahara" (nutriment) is defined in SN 12.11 and many more.

This is explained by Bhikkhu Sujato in his blog entry:

If we look closely at the terms in the jhana formula, then, we find that they are words that have a more coarse physical or psychological meaning in everyday language. They are common words that everyone can understand, and can relate to their own experience. And in every single case, they clearly have a more subtle, abstract, evolved meaning in the context of jhana. We have moved from the ordinary mind to the ‘higher mind’, and everything about the experience is transformed.

So, for example, the first word in the formula is viveka. This normally means physical seclusion; going away from others into the forest or a solitary spot. In jhana, however, it refers to a mental seclusion, where the mind turns away from the senses and withdraws into itself. The Pali texts make this distinction clear, as elsewhere they speak of three kinds of seclusion: physical, mental (i.e. the jhanas), and seclusion from all attachments (Awakening).

The next word in the formula is kama. In ordinary language this means the pleasures of life, especially sex, but also food, drink, luxuries, and other pleasures of the senses. In jhana, however, it has a more subtle nuance, referring to the mind that inclines to taking pleasure in any experience through the five senses.

Then there is the word akusala. Normally this means ‘unskilful’, as, for example, someone who is no good at a certain craft. One who is kusala, on the other hand, is clever and adroit. In the jhana formula, however, kusala includes any tendency of the mind that creates suffering.

Similarly there is the word dhamma, which is what akusala qualifies. Dhamma in ordinary language has a variety of meanings, such as ‘law’, ‘custom’, and so on. In jhana, however, it takes on a far more subtle meaning, that is, any object, quality, or tendency of the mind. The akusala-dhammas, or ‘unskilful qualities’, especially refer to the five hindrances which must be abandoned before entering jhana.

And so on. I could go on through the entire jhana formula and show how each word is related to, but abstracted from, its more concrete everyday basis, its ‘metaphier’. But I think that’s enough examples.