(idiomatic) An early period in development, infancy, the beginnings of something; inception.
Esimerkit
Luke 2:7 And she brought forth her firstborn son, and wrapped him in swaddling clothes, and laid him in a manger; because there was no room for them in the inn
The steel—industry wore swaddling clothes when the first walkout occurred exactly 100 years ago.
The Air Force Academy, baby brother to West Point and Annapolis, is crawling out of its swaddling clothes.