An insect that shares the essentials of life, like shelter, food, defense, and cooperation in reproduction: In the strict sense, a true social insect is one that belongs to a eusocial species; in other words, it is an ant, a termite, or one of the eusocial wasps or bees.

In the broad sense, a social insect is one that belongs to either a pre-social or eusocial species.