Describes something that feels tacked on, insincere, or not genuine, like a forced smile or an empty compliment. Often used with 笑顔, お世辞, 言い訳, etc.
彼の取って付けたような笑顔が気になった。
His forced smile bothered me.
そのお世辞は取って付けたようで、全然嬉しく
That compliment sounded so contrived that I wasn't happy at all.
不自然 is a more general word for 'unnatural', while 取って付けたよう specifically implies something added artificially and insincerely.
Standard kanji spelling; the phrase is often written with this kanji-kana mix.
Variant with つけた in kana; equally natural and common.
Uses 様 for よう; less common and slightly more formal or literary.
From the verb 取って付ける (to attach or add something), literally 'as if attached'. The phrase describes something that feels added on artificially rather than being a natural part.