also: やどぬし
Only with reading しゅくしゅ
Refers to an organism that harbors a parasite, mutualist, or commensal. Used in biological and ecological contexts.
ウイルスは宿主の細胞に侵入する。
The virus invades the host's cells.
この寄生虫は特定の宿主にしか感染しない。
This parasite only infects a specific host.
Only with reading やどぬし
Archaic or literary term for a person who provides lodging; now mostly replaced by 大家 (おおや) or 宿屋の主人. The reading やどぬし is explicitly associated with this sense.
旅人はやどぬしに部屋を案内された。
The traveler was shown to a room by the innkeeper.
昔話では、やどぬしが親切にもてなす場面がよく出てくる。
In old tales, scenes where the landlord kindly entertains guests often appear.
Refers to an inn itself, while 宿主 (やどぬし) refers to the person running it.
寄生虫 is the organism that lives off another, while 宿主 is the host organism it lives on or in.
Standard kanji form for the common reading しゅくしゅ, used in biology and general contexts.
Rare reading for the landlord/innkeeper sense; the kanji form is shared with the common reading しゅくしゅ.
Kana spelling for the landlord/innkeeper sense, avoiding confusion with the しゅくしゅ reading.
宿主 is a compound of 宿 (lodging, dwelling) and 主 (master, owner). The reading しゅくしゅ is the standard Sino-Japanese reading, while やどぬし is a native Japanese reading (kun'yomi) that directly reflects the meaning 'innkeeper' or 'landlord'. The biological sense is a modern extension of the 'host' concept.