Is the 月-like radical in 前{まえ} identical to 月?


I am a bit confused with the following facts.

![enter image description here](https://i.stack.imgur.com/WwnAn.png)

Is the 月-like radical in 前{まえ} identical to 月?




As you yourself observe, 月 looks different on its own than as an element in 前,
[in which it represents a simplification of
舟](http://chineseetymology.org/CharacterEtymology.aspx?submitButton1=Etymology&characterInput=%E5%89%8D).
So no, they are not identical.

As an element in other characters, the element that looks like 月 variously
represents other historical elements, including 肉, 舟, 丹, and 月 itself, among
others. In some characters the derivation is still significant in how they're
written--there are variants of 錆 where the lower-right 丹 was simplified to 円
instead of 月, for example. A _lot_ of characters contain this element, so we
can expect to see some variation in how it appears.

But we can try to find patterns. When does the left side curve? Here are my
observations, based entirely on how I perceive the current forms of the
characters, ignoring their history:

  1. 月 itself is written with a curve.

  2. In left-right characters where one side is written like 月, it is written with a curve:

月肋肌肘肝肚肛朋股肢肪服肬肭肱胎胞胆肺朏胖脉胙胚胛胝脂脇胴  
朕胸脈脆胱胼胯豚脱脚脳朖脛脯脹腔腕勝腆腑腋脾腓腰腫腺腹腸腱  
腦腮腟腿腴腥膜膀膈膊膃膝膵膣滕膕膤臟膓膠膨膳膩膰縢臈臆謄膽  
朦膾膿臉膸臍臑臓臘騰臚朧臙・明胡朔朋期朗朝

  3. In certain characters descended from the above, it's also written with a curve:

朋：萠崩堋棚弸繃鵬硼  
明：萌盟  
朝：廟潮嘲  
胡：湖楜瑚葫糊醐蝴餬  
朔：遡塑溯愬槊

滕：藤籐  
縢：籘  
服：箙  
豚：遯  
肋：筋

  4. In certain other characters it's also written with a curve:

望・覇霸・閒燗癇・羸瀛贏・朞

  5. The rest of the time, the left side of 月 is typically written straight:

有肖肓侑肴肯肩育青冐郁宥胤削背胃前胥胄陏囿屑哨宵脅脊骨俞能  
消娟悁涓捐兪峭悄狷脩梢情清剪猜脣偸逍淆菁揃喩随硝愉堕婿惰散  
晴渭渝喟隋壻稍揄靖楕膏熊煎潸滑賄腎絹瑜蛸骭逾楡睛錆聾體髑髓  
魘龕静猾愈精態榾趙誚蜻膂瘉骰酳厭撒請膚徹罷撤翦瘠銷磆箭墮蝓  
蝟籠襲髏鶺鶻霄龍謂靜鞘諭骸輸覦骼隨踰橢鮪膺臀鍮瀞壓蹐膸臂癒  
擶鵑繖髀擺羂鮹寵瀧髄蘢鯖羆壟隴轍霰瓏

These are just my own observations. They aren't intended to be taken as
absolute rules, and you may find variation in handwriting or in different
fonts. For example, I've noticed that in some fonts on my computer, 潸 falls
into category 4 instead of 5. But I think that overall the above is relatively
accurate.

