(1):

(adv. & a.) In a state of backwardness, in respect to what is seasonable or appropriate, or as to what should have been accomplished; not equally forward with some other person or thing; dilatory; backward; late; tardy; as, behindhand in studies or in work.

(2):

(adv. & a.) In arrears financially; in a state where expenditures have exceeded the receipt of funds.