Abstract
The linguistics gave birth to a new science – laсunology. The words and clusters of the lacunarity are described in this article. The ontology of lacunikon goes back to Greece, initiating the first cluster of lacunicon (i) liquid cluster of the lac- etymon, later there appeared the second cluster: lacuna cluster of the lac- etymon, (ii), then, the third lacuna cluster: lack/absence cluster of the lac- etymon, (iii) which is seen as pre-terminological cluster of the lacunicon. The author views the proсess of lacunae formation as semantic deviations of the systems of languages, defining close and near cognates of lacunicon in English and Ukrainian.
Keywords: lacunology thesaurus, lac-clusters, prototerms of lacunicon.