what is the meaning of "field return"?
The class is moved from the school room to another location where something of interest can be observed and perhaps more closely investigated for your edification. "Having a field day" is also used as a slang expression meaning that someone is having unfettered fun.
From the latin ager meaning field.
A field.
Field days.
SID in the medial field usually means Sudden Infant death.
In the field of biology, the meaning of the word "ontogeny" is the development and origin of an organism. You can get more information about this at the Wikipedia.
Field day originated with the military, speaking of a day that they spent in the field doing training and exercises. The first record of it being used to mean a day of frivolity was in 1827 in Thomas Creevey's Letters.
baseball field
What is the original meaning for armistice day
dry field
Field events are track-and-field contests other than races, such as throwing and jumping events.