御付き[otsuki] retainer
御墨付き[osumitsuki] handwriting
恰好付ける[kakkoutsukeru] to affect a stylish air
食っ付く[kuttsuku] to adhere to
食っ付ける[kuttsukeru] to attach

しがみ付く[shigamitsuku] to cling
何方付かず[docchitsukazu] gray area
に付いて[nitsuite] concerning
に付き[nitsuki] because of
打っ付ける[uchitsukeru] to knock

アナログデジタル変換器[anarogudejitaruhenkanki] analog-digital converter
データ交換[deetakoukan] data exchange
パリティ変換[paritihenkan] parity transformation (physics)
メール交換[meerukoukan] exchange of letters
意見交換[ikenkoukan] exchange of ideas

引換て[hikikaete] on the contrary
下位互換性[kaigokansei] downward compatibility
かな漢字変換[kanakanjihenkan] kana-kanji conversion (on a computer, etc.)
可換群[kakangun] Abelian group
賀詞交換[gashikoukan] New Year greetings (parties)