They are both synonyms. (falling down) There is a subtle difference though. 摔 - Has a more 'slipping' kind of implication. Like slipping off a cliff or on a banana peel. 跌 - Has a more 'tripping' kind of implication. Like catching your foot on a rock. (falling straight down) Those are the only differences and because it's really subtle, no one would correct you if you prefer the use of one over the other. Helps to know though !. (^____^) edit : There are some (rare) instances where you cannot substitute one for the other. Falling off a balcony you must use 摔。 It's strange to say 从阳台跌出去， but it makes sense if you say 从阳台摔出去。My guess is that even though it's a balcony, it's from a high place (like a cliff) and so must use 摔。 Probably helps to think that most balcony accidents start by someone 'slipping'. 跌 is also always used in an 'accident' context.摔 can be intentional. eg. 我们一起摔到了 = O 我们一起跌倒了 = O 我把他摔到了 = O 我把他跌倒了 = X (has to be accidental) 我害他摔到 = O 我害他跌倒 = O (It's your fault, but still an accident) Which is why wrestling is called 摔跤 and not 跌跤. Really though....no one will tend to correct you. Just take note of the 2 examples I gave you and you'll be fine. (^____^)

跤 其實是 骹 也就是脛 也就是小腿 摔跤 跌跤 通常是身體前仆 小腿先著地的動作 讀書若不求甚解 視為同義詞也可以含混過關 但 畢竟有別 摔 是棄於地 隱含力道強烈的意思 小明一進門 摔了書包 又往外跑了 飛機摔下來了 摔角是一種費力鬥智又鬥志的遊戲 因此 摔一跤 是形容重重的跌在地上 身子有如被強烈的力量摜倒 (摜 也是摔 扔之意) 陽台距離地面通常有三公尺以上 跌出陽台外 可能不足以形容落地時力道的強烈 摔出陽台外 除了力道 還有響亮的聲音 跌 是 失足 也就是足部失去根據 足既失根據 就會仆倒在地 跌一跤 有輕忽而無意間失足的意味 倒沒有重重的力量在其中的意思 大雄不聽勸告 依然在院子裡奔跑 結果狠狠的摔了一跤 我們不會用 狠狠的跌了一跤 因為 狠狠的 跟 跌一跤 有語意上的衝突 (力道 與 輕忽)

摔和跌是近意词 跤是作为名词 比如 摔了一跤 跌了一跤