buserelin

Etymology tree
Proto-Indo-European *tréyes
Proto-Indo-European *tri-
Proto-Indo-European *-tós
Proto-Indo-European *tritós
Proto-Italic *tritios
Latin tertiusder.
English tert-
Proto-Indo-European *gʷṓws
Proto-Hellenic *gʷous
Ancient Greek βοῦς (boûs)
Proto-Indo-European *tewh₂-
Proto-Indo-European *-rós
Proto-Indo-European *tuh₂rós
Proto-Hellenic *tūrós
Ancient Greek τῡρός (tūrós)
Ancient Greek βούτῡρος (boútūros)der.
English but-
Proto-Indo-European *swel-der.?
Ancient Greek ῡ̔́λη (hū́lē)der.
Frenchder.
English -yl
English butyl
English tert-butyl
Old Chinese 絲 (*sə)der.?
Ancient Greek σήρ (sḗr)
Proto-Indo-European *-kos
Ancient Greek -κός (-kós)
Ancient Greek -ῐκός (-ĭkós)
Ancient Greek σηρῐκός (sērĭkós)bor.
Latin sēricusder.
English serine
English release
Proto-Indo-European *-nós
Proto-Indo-European *-iHnos
Proto-Italic *-īnos
Latin -īnusder.
Old French -inbor.
Middle English -in
English -ineclip.
English -in
English -relin
English buserelin
From (tert-)bu(tyl) + se(rine) + -relin (“LHRH release–stimulating peptide”).