also: こんげつじゅうに
expression, adverb
by the end of this month; within this month
Expresses that something will happen or be completed at some point before the current month ends. Often used with deadlines or plans.
今月中にレポートを提出しなければならない。
I have to submit the report by the end of this month.
今月中に引っ越す予定です。
I plan to move within this month.
Compound of 今月 (this month) + 中 (within) + に (particle indicating time). The reading ちゅう is the standard on-reading of 中 in this temporal sense; じゅう is a variant.