In Greek nouns are inflected, they decline changing their form depending upon their case and number. A few nouns, usually loanwords recently borrowed from foreign languages, are indeclinable - all case forms are the same; in general (and correctly) the plural form will also be the same, although some, like φιλμ (film), may occasionally follow the originating language giving φιλμς (films).
In Greek, proper nouns are given names, surnames, placenames, demonyms, names of feasts, names of days and months, titles of works and synonyms of the Christian sense "God" and similar religious terms.
All proper nouns begin with an uppercase letter (capital).
Uppercase first letters are often used for emphasis or according to the preferences of the writer, on common nouns too.
See #Number for proper nouns.
Nouns may be classified into three genders: masculine, feminine and neuter. It is important to remember that grammatical gender is not the same as biological gender. Although in many cases these may be the same: άντρας (ántras, “man”) is masculine and γυναίκα (gynaíka, “woman”) is feminine, in others they are not: the words αγόρι (agóri, “boy”) and κορίτσι (korítsi, “girl”) are both neuter. In addition inanimate objects may be masculine or feminine although many are neuter; most loanwords are neuter. A fourth grammatical gender common, indicated in Wiktionary by "m, f ", is largely made up of nouns referring to occupations done by both men and women. Common nouns have a masculine endings but any articles or adjectives must agree with the gender of the person, thus for γιατρός m or f (giatrós, “doctor”): ο νέος γιατρός οr η νέα γιατρός. It should also be noted that γιατρός also exists in much less common feminine forms, a woman doctor may also be γιατρίνα (giatrína) or γιάτρισσα (giátrissa).
Most nouns have both singular and plural number.
There are few exceptions
Language names are common nouns, either feminine singular αγγλική (anglikí, “English”) by ellipsis of the feminine γλώσσα (glóssa, “language”), or neuter plural like αγγλικά n pl (angliká, “English”). In several Greek dictionaries they are found with uppercase first letter.
Given names, placenames, surnames also form both numbers:
For these, there are also exceptions: