Today we look at two more Spanish nouns which are identical in form apart from their endings but whose meanings are very different. These are foco (masculine) and foca (feminine).
Foco (masculine) is the commoner of the two and has many more meanings. You can listen to its pronunciation here:

Un foco is often a type of light – especially one that is focused on a particular place. It might be a floodlight in a stadium or a spotlight in a theatre, for instance:
Tres grandes focos iluminaron el terreno de juego.
Three big floodlights lit up the playing field.
Por fin, se vio bajo la luz de los focos.
She was finally in the spotlight.
De repente, los encargados de manejar los focos iluminan una parte del escenario.
Suddenly those in charge of the lighting or the lighting crew illuminate one area of the stage.
In parts of Latin America un foco might also be a headlight or headlamp on a vehicle:
Apagó los focos del bulldozer.
He turned off the bulldozer headlights.
Los focos de las motos no iluminan gran cosa.
Motorbike headlamps don’t give very good light.
los focos de estacionamiento
parking lights
In Mexico and some other parts of Latin America un foco might be what is called una bombilla elsewhere – a lightbulb:
El foco de la escalera permanecía encendido durante la noche.
The lightbulb over the staircase was left on all night.
Again in Latin America un foco might be a battery-powered, handheld cylindrical device equivalent to una linterna – a torch or flashlight:
los focos de los soldados
the soldiers’ torches
Away from the lights, el foco can be somewhere or something central to something, the focus or centre of it.
Un perro policía se ha convertido en el foco de atención aquí.
A police dog has become the focus or centre of attention here.
uno de los principales focos de investigación de materiales
one of the main focuses of research on materials
un verdadero foco de cultura
a real cultural hub
El foco might also be a place where something originates – the source of it:
Constituyen un foco constante de tensión e inseguridad.
They are a constant source of tension and insecurity.
Son un foco probable de infección.
They are a probable source of infection.
In visual and photographic contexts as well as in mathematical and scientific ones el foco often translates as focus:
¿Cómo se ajusta el foco?
How do you adjust the focus?
en el foco de la parábola
at the focus of the parabola
Now let’s move on to the less common foca (feminine), whose pronunciation you can listen to here:

Una foca (feminine) is a seal (of the marine mammal kind):
Hay una serie de animales en peligro de extinción y de los cuales destacan la foca y el visón.
There are a number of animals at risk of extinction including notably the seal and the mink.
una nutria o una foca
an otter or a seal
las focas monje del Mediterráneo
Mediterranean monk seals
DID YOU KNOW?
As we have seen, the grammatical gender of the Spanish word for seal is feminine. This has nothing to do with biological gender. To specify the sex of animals whose nouns do not change ending or grammatical gender according to biology, put macho after the noun for a male, and hembra after the noun for a female:
una foca macho, una foca hembra – unas focas machos, unas focas hembras
a male seal, a female seal – some male seals, some female seals.
un ratón macho, un ratón hembra – unos ratones machos, unos ratones hembras
a male rat, a female rat – some male rats, some female rats
Shao-Shao, la panda hembra del zoo de Madrid
Shao-Shao, Madrid Zoo’s female panda
el chicharreo de un grillo macho
the chirping of a male cricket
Los elefantes machos pueden llegar a tener seis toneladas de peso.
Male elephants can reach up to six tons in weight.
Alternatively, you can use macho de and hembra de with the name of the animal:
el caso de una hembra de hipopótamo que se negaba a bañarse
the case of a hippopotamus female or a female hippopotamus that wouldn’t wallow
tres machos de rata adulta
three adult male rats
To focus on more similar-looking Spanish nouns with different meanings, come back next week.