The Internal Vowel Alternation (IVA) system is commonly referred to as arbitrarily appearing in a small number of the so-called irregular noun plurals (e.g. goose-geese, mouse-mice) and past tense verb forms (e.g. sing-sang, take-took) in Modern English. But, historically, IVA was a prevalent and productive process in Old English in both the nominal and the verbal systems. In this paper, we will postulate that the IVA is a fullfledged sign system composed of a signal (signifiant) that is connected to a meaning (signifié) in the Saussurean sense. It has already been demonstrated that the IVA nominal and verbal forms are systematic phonologically (Even-Simkin and Tobin 2009). In this paper, we will present the semantic systems underlying the IVA forms. Beedham (2005: 114) argues that "[a]ll linguistic forms must fit into the system somehow, and they all must have a meaning, it is simply a case of working out how they fit in and what the meaning is". In this semantic analysis of the IVA forms we will show that the English IVA systems are both motivated and systematic semantically -i.e. that differences in form always imply differences in meaning (Bolinger 1977). We will maintain that each IVA pattern reflects a fundamental common semantic denominator. Thus our study connects the form-phonology and the meaning-semantics of the phenomenon of IVA as a full-fledged system of linguistic signs in English.KEY WORDS: IVA system, past tense verbs, noun plurals, semantic aspect.The two linguistic utterances [maen] and [mae:n] are the same word not because they are phonetically identical -they are not -but because we treat the difference between them as insignificant. On the other hand, the two utterances [maen] and [mɛn] count as different words despite their phonetic similarity because we treat the difference between them as significant. This social aspect of language Saussure dubbed langue. (Reid 2006:18) Brought to you by | HEC Bibliotheque Maryriam ET J. Authenticated Download Date | 6/16/15 11:37 PM Semantic denominators of the internal vowel alternation system 309 [...] the irregularity of the irregular verbs will disappear if we can find rules for them. If we find the meaning and the rules at all we will find them together, at the same time, because the linguistic sign is indivisible, i.e. form and meaning are indivisible.