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"La máquina" is a form of "máquina", a noun which is often translated as "machine". "El gato" is a form of "gato", a noun which is often translated as "cat". Learn more about the difference between "la máquina" and "el gato" below.
la máquina(
mah
-
kee
-
nah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (apparatus)
a. machine 
Hay que arreglar la máquina del taller para que podamos seguir con el trabajo.We need to fix the machine in the shop so that we can continue with our work.
2. (railway)
a. engine 
La máquina se descarriló en la curva, pero por fortuna no iba muy rápido.The engine derailed on the corner, but luckily it wasn't going very fast.
b. locomotive 
Mi tío es un fanático de las máquinas de vapor.My uncle is a steam locomotive fanatic.
a. car 
La mayoría de las máquinas que se ven en La Habana son de los años cincuenta.Most of the cars you see in Havana are from the fifties.
a. camera 
Me compré una máquina nueva para tomar fotos en la boda de mi mejor amigo.I bought a new camera to take pictures at my best friend's wedding.
5. (politics)
a. machine 
La máquina de Chicago ha ejercido poder por demasiados años.The Chicago machine has exercised power for too many years.
el gato, la gata(
gah
-
toh
)This means that the noun can be masculine or feminine, depending on the gender of the noun it refers to (e.g., el doctor, la doctora).
2. (pejorative) (personal attendant) (El Salvador) (Mexico)
An offensive word or phrase used to degrade a person or group of people based on race, gender, sexual preference, etc. (e.g., redneck).
Regionalism used in El Salvador
Regionalism used in Mexico
b. maid  (feminine)
Si quieres café, sírvetelo. No soy tu gata.If you want coffee, get it yourself. I'm not your maid.
a. person from Madrid 
¿Qué sabrá ese de flamenco? Es un gato.What does he know about flamenco? He's from Madrid.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
a. tic-tac-toe  (United States)
Regionalism used in the United States
Para jugar gato, solo necesitas un lápiz y un papel.To play tic-tac-toe, you just need a pencil and a piece of paper.
b. noughts and crosses  (United Kingdom)
Regionalism used in the United Kingdom
Necesitas una estrategia para ganar al gato.You need a strategy to win noughts and crosses.