応援【おうえん】
aid, assistance, help, support, reinforcement, cheering, rooting (for), support
支援【しえん】
support, backing, aid, assistance
援助【えんじょ】
assistance, aid, support
援護【えんご】
support, help, backing, covering (from enemy attack), protection
声援【せいえん】
(shout of) encouragement, cheering, rooting, support
援軍【えんぐん】
reinforcement
後援【こうえん】
support, backing
救援【きゅうえん】
relief, rescue
義援金【ぎえんきん】
donation money (esp. disaster relief or charity), contribution
無援【むえん】
helpless, unsupporting
援用【えんよう】
quotation (to support one's argument), citation (e.g. of a precedent), invocation, claim
増援【ぞうえん】
reinforcement (e.g. of troops)
来援【らいえん】
assistance, support