dek- / Indo-European roots
Examples of words with the root dek-: condign, dainty, decent, decorate, decorous, deign, dignify, dignity, diplodocus, disciple, disdain, docent, Docetism, docile, doctor, document, dogma, dowel, doxology, heterodox, indign, orthodox, pandect, paradox, synecdoche.
To take, accept.Oldest form *dek̑-, becoming *dek- in centum languages.
▲ Derivatives include decent, paradox, disdain.
1. Suffixed (stative) form *dek-ē-. decent from Latin decēre, to be fitting (< "to be acceptable").
2. Suffixed (causative) o-grade form *dok-eye-.
a. docent, docile, doctor, doctrine, document from Latin docēre, to teach (< "to cause to accept");
b. dogma, dogmatic; chionodoxa, Docetism, doxology, heterodox, orthodox, paradox from Greek dokein, to appear, seem, think (< "to cause to accept or be accepted").
3. Suffixed form *dek-es-.
a. décor, decorate from Latin decus, grace, ornament;
b. decorous from Latin decor, seemliness, elegance, beauty.
4. Suffixed form *dek-no-. dainty, deign, dignity; condign, dignify, disdain, indign, indignant, indignation from Latin dignus, worthy, deserving, fitting.
5. Reduplicated form *di-dk-ske-. disciple, discipline from Latin discere, to learn.
6. dowel, pandect, synecdoche from Greek dekhesthai, to accept.
7. Suffixed o-grade form *dok-o-. diplodocus from Greek dokos, beam, support.
[Pokorny 1. dek̑- 189.]