[どうじに, doujini] (adv, conj) coincident with; while; simultaneously #1339
[かさなる, kasanaru] (v5r, vi) (1) to be piled up; to lie on top of one another; (2) to come one after another; to happen over and over; to pile up (e.g. stress); to accumulate; (3) to overlap (each other); to occur at the same time; to happen simultaneously; (P) #15948
[かねる, kaneru] (aux-v) (1) (See 兼ねない) to be unable to (usu. kana); to find difficult (unpleasant, awkward, painful) to do (usu. kana); (v1, vt) (2) to serve two or more functions or roles simultaneously; to contain (or combine) two or more features; (3) to work in two or more jobs simultaneously (positions, etc.); to do alongside; (4) to hesitate to do something (out of consideration for others); (5) to think of the future (as well as the present); (P) #17407
[あぶはちとらず, abuhachitorazu] (n) attempting two tasks simultaneously, accomplishing neither
[いちどきに;いちじに;いっときに, ichidokini ; ichijini ; ittokini] (adv) at the same time; at a time; at one time; simultaneously
[いっせいに, isseini] (adv) simultaneously; all at once; (P)
[けんえい, ken'ei] (n, vs) operating or carrying on simultaneously
[けんこう, kenkou] (n, vs) doing simultaneously
[けんけんがくがく, kenkengakugaku] (adj-t, adv-to) (See 侃々諤々, 喧々囂々) tumultuous (with everyone voicing their opinions simultaneously); uproarious
[じゅうふくりっこうほ, juufukurikkouho] (n) simultaneously running for a seat in a single-member constituency and a seat in a proportionally representated constituency