also: るすのま
expression, noun which may take the genitive case particle 'no'
during one's absence; while away
Used as a noun phrase or adjectival expression to refer to the period when someone is not present. Often followed by に to indicate 'while someone is away'.
A package arrived while I was away.
I took care of his dog during his absence.
Standard kanji spelling for the reading るすのあいだ.
Alternate reading るすのま; less common and may sound slightly old-fashioned or formal.
Mixed kanji-kana spelling; the kana あいだ may be used for clarity or emphasis.
Compound of 留守 (absence) + の (possessive particle) + 間 (interval, period). The reading あいだ is standard; ま is an older, less common reading for 間 in this context.