OS diaper
In real, traceable use. Part of the curated seed collection; community review is coming.
Meaning · English
Abbreviation of one-size diaper (“a type of cloth diaper which can be adjusted and lengthened to match the baby's growth, thus allowing the diaper to be worn from around birth (by a newborn) to potty-training age”).
Register: slang
Where it’s used:
Used
American English
Examples
Depending on the shape of your baby, OS diapers may not fit the entire range listed. For example, a lot of OS cloth diapers claim they fit from birth to potty training. This is sometimes the case but not always. My first child didn't start to fit (very well) into his OS diapers until he was around 1
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “OS diaper” mean?
Abbreviation of one-size diaper (“a type of cloth diaper which can be adjusted and lengthened to match the baby's growth, thus allowing the diaper to be worn from around birth (by a newborn) to potty-training age”).
Is “OS diaper” formal or informal?
OS diaper is generally slang.