An Etymological Dictionary of Astronomy and Astrophysics

A suffix meaning “small, little,” as in → formula, → globule, → module, capsule, nodule.

Etymology (EN): From Fr. -ule, from L. diminutive suffix -ulus (feminine -ula, neuter -ulum).

Etymology (PE): Pers. diminutive suffix -ul, ulé, as in:
zangulé, zangul “small bell;”
kutulé, kutul “dwarf;”
golulé, gullé “small ball; bullet;”
maškulé (Torbat Heydariye-yi) “small water-skin;”
kandulé “a small jar for holding grain;”
jâšulé = small donkey (Kurd.);
Ahmadulé = little Ahmad (Kurd.);
rulé = “little child” (Kurd., Tâleši, Borujerdi, Malâyeri,
and other Western dialects of Iran) probably from *ruduleh, cf. rud “child” (in zâd-o-rud) and Gilaki rey “boy;”
digul (Šuštari), digulé (Qomi) “small casserole, little pot;”

This suffix occurs also as -ulu, -âlé, and -élé as, e.g., in
kuculu, cangul, panjul, bozqâlé, dâsqâlé,
kâselé (Farâhâni) “small bowl,” and
barfelé (Farâhâni) “little snow.”

Examples of use in this dictionary:
disul → formula;
karpul → corpuscle.

See also -al → -al