The given series is:
\[
240, ?, 120, 40, 10, 2
\]
We can observe that each term is divided by a constant factor to get the next term:
\( 240 \div 2 = 120 \)
\( 120 \div 3 = 40 \)
\( 40 \div 4 = 10 \)
\( 10 \div 5 = 2 \)
Thus, the missing term must be \( 240 \div 2 = 120 \), which follows the consistent pattern of division by increasing factors.
Therefore, the missing term is 240.