noun
monaka; wafer cake filled with bean jam
A traditional Japanese sweet consisting of crisp wafers with sweet azuki bean jam inside.
お土産に最中を買ってきた。
I bought some monaka as a souvenir.
noun
in the middle of; in the midst of; at the height of
Literary or poetic expression for being in the middle of an action or state. Often used in the form 〜の最中に.
会議の最中に電話が鳴った。
The phone rang in the middle of the meeting.
さいちゅう is the common modern word for 'in the middle of', while もなか in this sense is literary and less frequent.
The sweet's name is said to come from a poem where a courtier described the moon as being 'in the middle of' (最中) a round rice cake, but the exact derivation is uncertain.