Geminates, the appearance of which is the result neither of ancient inheritance and loanwords, nor of any intra-dialect procedure such as assimilations, analogical extensions etc. are considered “spontaneous” (Newton 1968). The aim of this paper is twofold: firstly, there will be an attempt to critically review previous synchronic proposals on spontaneous gemination (concluding that none of these proposals is able to cover all aspects of the phenomenon) and, secondly, it will be shown, through a diachronic and cross-dialect description of the phenomenon, that many Cypriot Greek geminates that were previously regarded as spontaneous can actually be attributed to several other causes. Spontaneous forms are divided into two groups: one includes older forms that are common in the so-called geminating Modern Greek dialects and also occur in medieval texts and the other includes recently geminated forms, not presented in the relevant literature so far. ΛΕΞΕΙΣ-ΚΛΕΙΔΙΑ: διπλά σύμφωνα, κυπριακή διάλεκτος, μη αιτιολογημένος διπλασιασμός