-at-

Etymology
The a vowel of present-tense -as plus the t of the Latin/Romance/German passive perfect participle.

Suffix

 * 1)  -ato One who undergoes the action of the root
 * 2)  -ata The passive present participle
 * 3)  -ate The passive present participle
 * 1)  -ate The passive present participle
 * 1)  -ate The passive present participle
 * 1)  -ate The passive present participle

Affix

 * 1) make one do something
 * 2) explicitly makes a verb transitive