layer up
/lˈeɪəɹ ˈʌp/
/lˈeɪɚɹ ˈʌp/
Etymology
Old FrenchMiddle EnglishModern English
Formed from the noun 'layer' (meaning a single thickness of material) used as a verb, combined with the particle 'up' to create a phrasal verb meaning 'to add layers'. The noun 'layer' comes from Middle English 'leier', from Old French 'lier' (to bind), influenced by the idea of things lying one on top of another.