The
suffix "
ling" is very rarely used to denote a
diminutive form of an English
noun. This particular usage was probably popularised in 50s
sci-fi. While it doesn't exactly fit the pattern of
duckling,
sapling and
underling, it really has no other
siblings in English.
Usage of "ling" as a
diminutive suffix comes from
German, where it's equivalent - "lein" - is still quite common.
If anyone knows anything about this Drummond chap mentioned in Webster's writeup, please message me.