¿Cómo encontrar el género de una palabra?
How to find the gender of a word? Is there any rules ?
4 Answers
In general, you can follow this rule: Words that end in -o or -e are masculine, and words that end in -a are feminine. However, there are many, many, many exceptions, so don't rely entirely on that rule.
Check out this reference article. It should help you 
Most of the time, words ending with -d or -z are feminine.
Words ending in -ción are always feminine.
However, as with everything in Spanish, there are exceptions to rules. I suggest studying the word very thoroughly to make sure you know its gender. When in doubt, check the dictionary. It will say "masculine noun" or "feminine noun"...something like that to indicate the word's gender.
Good question. I hope I helped
As has already been suggested, there are several noticeable patterns in regards to endings which can be observed, the most prominent of these being those mentioned by Lazarus, i.e. those ending in -o (mostly masculine) and those ending in -a (mostly feminine with many exceptions in words of Greek origin).
Aside from these, you also see a few other patterns that vary with regards to predictability:
Feminine:
-ora, -esa, -isa, -ina, -dad, -tad, -tud, -umbre, -ción, -sión, -triz
Masculine: -dor, -tor, -ismo
There are probably numerous other examples that can be listed, but the problem is that many of these morphemes are not always reliable predictors of gender. The best way to be sure would be to simply consult a dictionary and to learn the gender when you learn the word.
One important thing to consider is that In terms of gender systems, the gender of a noun is not a property that can always be observed in the noun itself. That is when we break down the structure of various nouns, gender is not always exhibited morphologically by the noun.
Instead, gender can often be looked at as a quality that is demonstrated in the agreement that occurs between a noun and other inflected parts of speech such as adjectives, articles and other determiners. I will give a few examples:
?La niña — the girl [fem.]
?El niño — the boy [masc.]
?El ladrón — the (male) thief [masc.]
?La ladrona — the (female) thief [fem.]
It is reasonable to argue here that the noun carries inflectional endings (-a and -o) which indicate the gender of the noun. However, examining the following noun phrases demonstrates that gender does not always appear in the noun itself but is demonstrated by the agreement that occurs between the noun and (in this case) its article:
?El rumor — the rumor [masc.]
?La flor — the flower [fem.]
This becomes even more apparent when we start dealing with nouns that differentiate gender based on the sex of an individual but that remain invariable in form (often referred to as "common nouns, with respect to gender"). These nouns do not inflect to show gender, as with niño/niña, but instead, gender is evidenced by the agreement that occurs between the noun and other parts of speech:
?La cantante — the (female) singer [com.]
?El cantante — the (male) singer [com.]
?La agente — the (female) agent [com.]
?El agente — the (male) agent [com.]
Still other nouns, termed "ambiguous with respect to gender," can take either a masculine or feminine article (although one is often preferred). A few examples of these include:
?El/la mar — the sea [amb.]
?El/la vodka — the vodka [amb.]
?El/la azúcar — the sugar [amb.]
You might also look up the idea of epicene nouns (sustantivos epicenos) which probably does not relate directly to your question but that you might find informative nonetheless.
You can look it up in the dictionary. Normaly they put s.f. (sustantivo femenino) if the noun is femenine, and s.m. (sustantivo masculino) if it is masculine.
Sometimes they just put f. or m., but remember that only the nouns have a gender. The articles and the adjectives must agree with the gender of the noun: el niño travieso; la niña traviesa.
In general, you can follow this rule: Words that end in -o or -e are masculine, and words that end in -a are feminine.
Almost all words ending in -o are masculine. The most important exceptions are "mano", "foto" (short for "fotografía"), "moto" (short for "motocicleta"), "radio" (short for "radiodifusión") and "virago".
Now, many words ending in -a are feminine, but there are many hundreds that can also be masculine, so you have to be more careful with this one.
Words ending in -ción are always feminine.
Not those with the augmentative suffix -ión: el notición, el sentención, el roción...
