If you're curious about Greek: loanwords are mostly gendered as neuter, and because their endings usually don't match Greek noun endings, are treated as opaque/invariable units that don't participate in the usual system of noun cases (meaning genitive, nominative, etc. cases are all identical and not declined). Examples: ασανσέρ (asansér, elevator, from French ascenseur), ουίσκι (ouíski, whiskey). This is especially true for recent loanwords.
Older loanwords were sometimes 'Hellenized' into a Greek ending and gender. Example: Turkish cep became Greek τσέπη (tsépi, pocket, feminine), French canapé became Greek καναπές (kanapés, couch, masculine), and Turkish pabuç became Greek παπούτσι (papoútsi, shoe, neuter). These are then declined according to the noun class they were assimilated into.
Another category are words whose ending is translated to the semantically equivalent Greek ending, for example any -ism (capitalism, communism, feminism) will become an -ισμός, which is masculine.
Older loanwords were sometimes 'Hellenized' into a Greek ending and gender. Example: Turkish cep became Greek τσέπη (tsépi, pocket, feminine), French canapé became Greek καναπές (kanapés, couch, masculine), and Turkish pabuç became Greek παπούτσι (papoútsi, shoe, neuter). These are then declined according to the noun class they were assimilated into.
Another category are words whose ending is translated to the semantically equivalent Greek ending, for example any -ism (capitalism, communism, feminism) will become an -ισμός, which is masculine.