Les animaux

Une bête is a beast or an animal. Bête as an adjective means stupid. And c'est bête means that is a shame, which is a third thing again.

• Une bête sauvage. A wild animal.
• Il est bête. He is stupid.
• C'est bête, j'ai oublié. That is annoying, I forgot.

Context separates them without much trouble, but it is worth knowing before you describe somebody's dog as bête and watch their face.

Pets

Un animal familier or un animal de compagnie is a pet. There is no single short word, which surprises English speakers who expect one.

Un chien and un chat have feminine forms, une chienne and une chatte, and both carry vulgar secondary meanings in French exactly as one of them does in English. Use them with the same care.

Grammatical gender is not biological

Most animals have a fixed grammatical gender regardless of the creature in front of you. Une souris is always feminine, un serpent always masculine. To specify you add mâle or femelle: une souris mâle is perfectly normal.

Only the familiar farm and domestic animals have real pairs: chien and chienne, chat and chatte, cheval and jument.

Noises

French animals make different noises, and the verbs are specific: a dog aboie, a cat miaule, a cow meugle, a bird chante. English collapses several of these into generic verbs; French does not.

The pig has two words

Un cochon is the animal. Le porc is the meat, and also the animal in a more formal or agricultural register. The same split runs through French cooking vocabulary and is a relic of Norman French sitting on top of Anglo-Saxon, which is where English got beef and pork in the first place.