What is the difference between 型 and 形?


What is the difference between 型 and 形? I was taught that 型 means something
like "form" and 形 means shape/form、and I wonder, are they interchangeable?
Does 型 only come after a word or phrase?




By definition, 型 means _die_ , _matrix_ , _model_ , _mold_ , or a tool to cast
something into a certain shape. 形 means, as you said, _form_ , _figure_ ,
_shape_ or the overall outline an object has. And naturally, 型 has an extended
meaning just like that of English _model_ (or _type_ , _pattern_ etc.) which
stand for discrete classification of objects by certain criteria, as if they
share the same original caster.

They have same pronunciation as suffixes (both kun'yomi: がた and on'yomi: けい),
but whenever you see ○○型, you should expect the literal translation _○○-type_
, while ○○形 is _○○-shaped_. This is the basic idea. Of course some "types" are
based on nothing more than visual appearances, in which case 型 and 形 are
interchangeable, but not always. Also note that 形 can be used as a suffix only
when you mention the physical shape.

> 地球 **型** 惑星 _terrestrial planet_ (whose composition is like the Earth; all
> planets have the same round silhouette shape-wise)
>
> 夜 **型** 人間 _night owl_ (who has nocturnal trait; nobody looks like the
> night)
>
> 楔 **形** 文字 _cuneiform_ (whose shape is like wedges; they are otherwise not
> related to wedges)
>
> 円 **形** 脱毛症 _alopecia areata_ (or _spot baldness_ : whose shape is more or
> less round)

and... [![enter image description
here](https://i.stack.imgur.com/eQo74.jpg)](https://i.stack.imgur.com/eQo74.jpg)




By definition, 型 means _die_ , _matrix_ , _model_ , _mold_ , or a tool to cast
something into a certain shape. 形 means, as you said, _form_ , _figure_ ,
_shape_ or the overall outline an object has. And naturally, 型 has an extended
meaning just like that of English _model_ (or _type_ , _pattern_ etc.) which
stand for discrete classification of objects by certain criteria, as if they
share the same original caster.

They have same pronunciation as suffixes (both kun'yomi: がた and on'yomi: けい),
but whenever you see ○○型, you should expect the literal translation _○○-type_
, while ○○形 is _○○-shaped_. This is the basic idea. Of course some "types" are
based on nothing more than visual appearances, in which case 型 and 形 are
interchangeable, but not always. Also note that 形 can be used as a suffix only
when you mention the physical shape.

> 地球 **型** 惑星 _terrestrial planet_ (whose composition is like the Earth; all
> planets have the same round silhouette shape-wise)
>
> 夜 **型** 人間 _night owl_ (who has nocturnal trait; nobody looks like the
> night)
>
> 楔 **形** 文字 _cuneiform_ (whose shape is like wedges; they are otherwise not
> related to wedges)
>
> 円 **形** 脱毛症 _alopecia areata_ (or _spot baldness_ : whose shape is more or
> less round)

and... [![enter image description
here](https://i.stack.imgur.com/eQo74.jpg)](https://i.stack.imgur.com/eQo74.jpg)

