English
lambswool
From lamb + -s- + wool.
Proto-Germanic *lambaz
Proto-West Germanic *lamb
Old English lamb
Middle English lamb ‘a lamb, its meat, or its skin’
English lamb
Proto-Indo-European *h₂welh₁- ‘hair’
…
Proto-Germanic *wullō
Proto-West Germanic *wullu
Old English wull
Middle English wolle ‘wool, especially when used to make fabric’
English wool
Today it means
noun The wool of a lamb.
Language periods are conventional ranges, not dates for this word.
Etymograph / lambswool