pattern - What is a Composite Word™?

Here are some Composite Words™:

ADEPTIO           DIVTVRNVS
EXILIS            MIXTVM
CVLTELLVS         ARMARIVM
ACERBVS           ALIOQVI
IMPRAESENTIARVM   CVRVVS
AMICVS            CONCVLCO
LACRIMABILIS      ABVNDANS

ADDO              ADEO
IMMVNDVS          INFLECTVM
ALTVS             LIQVIDVS

Here are some non-Composite Words™:

ANTIQVVS          LVXVRIA
AMICVLVM          CRINITVS
ABSQVE            IVDICIVM
MVNIMENTVM        EXCELLENTIA
CALLIDE           ECCLESIA

AMICITIA          MAXIME
IMPRIMIS          ALIQVANTVS
HAFFLIGENIENSIS   INCLITVS
CALAMITAS         CONIVRATVS
BAIVLVS           ARTIFICIOSE

What property determines if I call it a Composite Word™ or not?

Answer

Composite words are those where the

sum of the Roman numeral values of the contained letters IVXLCDM

is equal to

a composite number.

The relevant data for each word:

ADEPTIO 501 [3, 167] DIVTVRNVS 516 [2, 2, 3, 43] EXILIS 62 [2, 31] MIXTVM 2016 [2, 2, 2, 2, 2, 3, 3, 7] CVLTELLVS 260 [2, 2, 5, 13] ARMARIVM 2006 [2, 17, 59] ACERBVS 105 [3, 5, 7] ALIOQVI 57 [3, 19] IMPRAESENTIARVM 2007 [3, 3, 223] CVRVVS 115 [5, 23] AMICVS 1106 [2, 7, 79] CONCVLCO 355 [5, 71] LACRIMABILIS 1203 [3, 401] ABVNDANS 505 [5, 101] ADDO 1000 [2, 2, 2, 5, 5, 5] ADEO 500 [2, 2, 5, 5, 5] IMMVNDVS 2511 [3, 3, 3, 3, 31] INFLECTVM 1156 [2, 2, 17, 17] ALTVS 55 [5, 11] LIQVIDVS 562 [2, 281] ANTIQVVS 11 [11] LVXVRIA 71 [71] AMICVLVM 2161 [2161] CRINITVS 107 [107] ABSQVE 5 [5] IVDICIVM 1613 [1613] MVNIMENTVM 3011 [3011] EXCELLENTIA 211 [211] CALLIDE 701 [701] ECCLESIA 251 [251] AMICITIA 1103 [1103] MAXIME 2011 [2011] IMPRIMIS 2003 [2003] ALIQVANTVS 61 [61] HAFFLIGENIENSIS 53 [53] INCLITVS 157 [157] CALAMITAS 1151 [1151] CONIVRATVS 111 [3, 37] BAIVLVS 61 [61] ARTIFICIOSE 103 [103]