Refers specifically to the peppermint plant (Mentha × piperita). Often used in contexts of herbs, teas, and essential oils.
See also: ペパーミント
Peppermint essential oil has a refreshing scent.
This herbal tea contains peppermint.
ペパーミント is a more common loanword for peppermint, especially in product names and casual contexts. セイヨウハッカ is the formal Japanese name for the plant.
薄荷 is the general term for mint plants. セイヨウハッカ specifies the Western peppermint variety.
Katakana spelling is standard for this plant name.
Kanji spelling is rare; the word is usually written in kana.
Compound of 西洋 (seiyō, 'Western') and 薄荷 (hakka, 'mint'). The reading はっか is a sound change from はくか.