Atheism is a term that implies, simply, a theism. From the Greek, A (without) and theos (gods). The term atheism itself, from the French athéisme originated probably in the 16th Century C.E. and it's use peaked during the 1800's, diminished substantially in the 1900's but continues today.

The definition, however, in it's modern use, is often given as simply "disbelief or lack of belief in the existence of gods," a nonsensical application since the word god, in the ancient Hebrew, Common Greek, Latin and English, simply means anyone or anything that is considered mighty or that is venerated.

Dictionary Definition Of Gods

1. (in Christianity and other monotheistic religions) the creator and ruler of the universe and source of all moral authority; the supreme being.

2. (in certain other religions) a superhuman being or spirit worshiped as having power over nature or human fortunes; a deity.

3. an adored, admired, or influential person.

4. the gallery in a theater.

So, there are many gods, making the term atheism, by definition, a misnomer.