<horned animal> stag beetle 18 realizations
NEW Realization 1
type Derivation
language Asturian
lexeme 1 vaca
lexeme 2 vacalloria
meaning 1 cow
direction
meaning 2 stag beetle
reference Corominas, Pascual
comment

See Galician

NEW Realization 2
type Polysemy
language Bulgarian
lexeme рогач
meaning 1 stag
direction
meaning 2 stag beetle
reference RNBE
comment
NEW Realization 3
type Derivation
language Dutch
lexeme 1 hert
lexeme 2 vliegend hert
meaning 1 deer
direction
meaning 2 stag beetle
reference HWNF
comment
NEW Realization 4
type Derivation
language English
lexeme 1 stag
lexeme 2 stag beetle
meaning 1 adult male deer, especially a red deer and especially one in high adulthood versus a young adult
direction
meaning 2 any of numerous large beetles of the family Lucanidae, the males having elaborate mandibles resembling the antlers of a stag especially, the beetle of species Lucanus cervus.
reference OED
comment
NEW Realization 5
type Derivation
language Finnish
lexeme 1 härkä + tammi
lexeme 2 tammihärkä
meaning 1 ox + oak
direction
meaning 2 stag beetle
reference Kielitoimiston sanakirja
comment
NEW Realization 6
type Derivation
language French
lexeme 1 cerf
lexeme 2 cerf-volant
meaning 1 deer, stag
direction
meaning 2 stag beetle
reference CNRTL
comment
NEW Realization 7
type Derivation
language Galician
lexeme 1 vaca
lexeme 2 vacaloura
meaning 1 cow
direction
meaning 2 stag beetle
reference Corominas, Pascual DDDDLG
comment

Apparently a composite of vaca (“cow”) + loura (in the past, "dark"); so either "dark cow" or perhaps a folk etymology of an older composite pre-Latin word

Antón Luís Santamarina Fernández, Ernesto Xosé González Seoane, María Álvarez de la Granja, editors (2003–2018), Tesouro informatizado da lingua galega, Santiago de Compostela: Instituto da Lingua Galega https://ilg.usc.gal/TILG/en/search/?utf8=%E2%9C%93&result_type=kwic&search_type=units&text=vacaloura 
Rosario Álvarez Blanco, editor (2014–2024) Tesouro do léxico patrimonial galego e portugués (in Galician), Santiago de Compostela: Instituto da Lingua Galega http://ilg.usc.gal/tesouro/en/search#search=normal&mode=lema&q=vacaloura 

NEW Realization 8
type Derivation
language Galician
lexeme 1 bois + escornar
lexeme 2 escornabois
meaning 1 oxen + to gore
direction
meaning 2 stag beetle
reference DDDDLG
comment

Antón Luís Santamarina Fernández, Ernesto Xosé González Seoane, María Álvarez de la Granja, editors (2003–2018) Tesouro informatizado da lingua galega (in Galician), Santiago de Compostela: Instituto da Lingua Galega https://ilg.usc.gal/TILG/en/search/?utf8=%E2%9C%93&result_type=kwic&search_type=units&text=escornabois 
Rosario Álvarez Blanco, editor (2014–2024) Tesouro do léxico patrimonial galego e portugués (in Galician), Santiago de Compostela: Instituto da Lingua Galega http://ilg.usc.gal/tesouro/en/search#search=normal&mode=lema&q=escornabois 

NEW Realization 9
type Derivation
language German
lexeme 1 Hirsch + Käfer
lexeme 2 Hirschkäfer
meaning 1 stag + beetle
direction
meaning 2 stag beetle
reference DWDS Duden
comment
NEW Realization 10
type Derivation
language Hungarian
lexeme 1 szarvas + bogár
lexeme 2 szarvas
meaning 1 deer + beetle
direction
meaning 2 stag beetle
reference Gal’di 1987
comment
NEW Realization 11
type Polysemy
language Polish
lexeme jelonek
meaning 1 diminutive of jeleń 'stag, deer'
direction
meaning 2 stag beetle
reference WSJP
comment

Also jelonek rogacz

NEW Realization 12
type Derivation
language Portuguese
lexeme 1 vaca
lexeme 2 vacaloura
meaning 1 cow
direction
meaning 2 stag beetle
reference DPLP
comment

See Galician

NEW Realization 13
type Derivation
language Romanian
lexeme 1 cerb
lexeme 2 cerbar
meaning 1 deer
direction
meaning 2 (regional, popular) stag beetle (Lucanus cervus)
reference MDA2
comment
NEW Realization 14
type Polysemy
language Romanian
lexeme taur
meaning 1 bull (uncastrated adult male of cattle)
direction
meaning 2 (popular) stag beetle
reference MDA2
comment
NEW Realization 15
type Derivation
language Russian
lexeme 1 олень
lexeme 2 жук-олень
meaning 1 deer
direction
meaning 2 stag beetle
reference <personally collected data>
comment

Стриганова Б. Р., Захаров А. А. Пятиязычный словарь названий животных: Насекомые. Латинский, русский, английский, немецкий, французский / под ред. д-ра биол. наук, проф. Б. Р. Стригановой. — М.: РУССО, 2000. — С. 113

NEW Realization 16
type Polysemy
language Russian
lexeme 1 рогвч
lexeme 2 рогач
meaning 1 stag
direction
meaning 2 stag beetle
reference <personally collected data>
comment
NEW Realization 17
type Derivation
language Spanish
lexeme 1 ciervo
lexeme 2 ciervo volante
meaning 1 deer, stag
direction
meaning 2 stag beetle
reference DRAE
comment
NEW Realization 18
type Derivation
language Swedish
lexeme 1 oxe + ek
lexeme 2 ekoxe
meaning 1 ox + oak
direction
meaning 2 stag beetle
reference SAOB
comment