Bee

The word bee, part of the English language since before the 12th century, has its origins in Proto-Indo-European (PIE) bhei (bee) and Proto-Germanic bion, the source of Old Norse by, Old High German bia, Middle Dutch bie, and Old English beo.
 
The word bee is an etymon; i.e., a word that has not changed that much since its origins thousands of years ago.
 
There are several metaphors that include bee; e.g., ‘busy as a bee’ (1530s), ‘to have a bee in one’s bonnet’ (1553), the ‘birds and the bees’ (late 19th century), and ‘to make a bee line’ (date unknown).
 
However, these metaphors are not to be confused with other expressions which do not come from bee but are from Middle English bene (good, well) and boon (blessing, benefit, favor); e.g., a ‘work bee’ (1769, a meeting of neighbours to unite their labor for one of their number), a ‘spelling bee’ (1809), a ‘raising bee’ (1814, related to building construction), ‘quilting bee’ from 1824, and, incredulously, extraordinarily, sadly, the phrase ‘hanging bee’ (sometimes called a ‘lynching picnic’) from the 19th century United States.
 
Reference: Online Etymological Dictionary, https://www.etymonline.com/
​