Last name Decem (Des 
, Decem 
, Decano 
) , in the world, is a common surname. The surname Decem is characteristic of Philippines, where it is quite a rare surname, Oman, and United Arab Emirates. Not in comparison with a country's population, it is commonest in Philippines, Indonesia, and France. More frequently, Decem is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Des | Australia, Philippines, Indonesia, Myanmar, India |
| Decem | Philippines, China, United States, Myanmar, India |
| Decano | Philippines, United States, Italy, Saudi Arabia, United Arab Emirates |
| Deán | South Africa |
Dean, Dece, December, Decemvir, Decennial, Deceno, Deche, Deci, Decuman, Decury, Deghe, Degà, Dek, Deken, Denarian, Deni, Desch, Desember, Desè, Deu, Dez, Dezasseis, Dezember, Dgix, Dhjetor, Diciembre, Dicker, Diece, Dieci, Diesch, Diese, Diez, Diezmo, Dijh, Dinou, Disset, Disyembre, Divuit, Dix, Doyen, Dozen, Dyez, Dzatsi, Dés, Dîs, Gise, Gize, Ten, Zece, Đêcêm, Đêĉëm, Декабрь, Децем, Дюжина, and ديسيمبر
Ko, Novem, Yeung, Arengh, Cheung, Ferrer, Sanchez, Suladay, Leung, Reginio, Daniyal, Gallosa, Guarino, Senerado, Balanday, Galdones, Lasalita, Rupinta, Santotome, Reyes, Payot, Na, Moe, Bar, Ber, Lai, Lay, Lee, Rosas, Jue, Wun, Chan, Hung, Wong, Yuen, Marak, Cheng, Teo, and Palaganas