Where does “nappy liner” come from?

nappy liner (English) comes from English nappy, from English NAP, from French napper, from French -er, from English -er, from Middle English -er, from Old French -er, from Latin -āre — he, she.

Ancestry of “nappy liner”, step by step

nappy liner traces back through two separate lines of ancestry.

via English nappy

StepLanguageWordMeaning
1EnglishnappyAn absorbent garment worn by a baby who does not...
2EnglishNAPAcronym of non-aggression principle; Acronym of...
3Frenchnapperto cover
4French-erForms infinitives of first-conjugation verbs
5English-erA person or thing that does an action indicated...
6Middle English-eragentive suffix; agent noun suffix
7Old French-erAlternative form of -ier, verbal suffix;...
8Latin-ārefirst conjugation
9Proto-Italic-āōForms primarily denominative verbs
10Proto-Indo-European-eh₂yétiCreates iterative/ frequentative/ intensive...
11Proto-Indo-European-yétiCreates intransitive, often deponent,...
12Proto-Indo-Europeanyé-
13Chichewaiyehe, she

via English liner

StepLanguageWordMeaning
1EnglishlinerSomeone who fits a lining to something; A...
2EnglishlineA path through two or more points (compare ‘segment’); a continuous mark, including as made by a pen; any path, curved or straight
3Middle Englishlinerope, cord; line, rule, ruler, measure; rule,...
4Old Englishlīneline, rope, cord; line, cable, rope, hawser,...
5Proto-West Germanic*līnāline, chord, rope, string
6Proto-Germaniclīnǭthat which is made of flax; line, chord, rope,...
7Proto-Germaniclīnąflax
8Proto-Indo-Europeanlīno-flax
Every word from Chichewa iye