The only free and comprehensive online etymological dictionary of the Spanish language
militar (2) (Verb) "to serve (in the military)"
Late 15th cent. From Latin militare 'id.' From miles "soldier." Of unknown origin.
Portuguese militar, French militer, Italian militare
milla f. (Noun) "mile"
Late 15th cent. From Latin milia "thousand," refering to a thousand steps in a mile. See mil for further etymology.
millón m. (Cardinal Number) "million"
15th cent. borrowing from French million, which was borrowed from Old Italian milion 'id.' From Latin mille "thousand" (see mil) and augmentive suffix -one (see -ón).
mimar (Verb) "to pamper"
Very late 15th cent. Derived from mimo (1).
mimo (1) m. (Noun) "carress"
16th cent. Of unknown origin, probably imitative of petting.
mimo (2) m. (Noun) "mime"
16th cent. From Latin mimus 'id.' Borrowed from Ancient Greek μῖμος (mîmos) 'id.' Of unknown origin. Beekes (2014) believes the word is from Pre-Greek.
French mime, Italian mimo
ministro m. (Noun) "minister"
13th cent. From Latin minister "servant." From Proto-Italic *minos-tero- "servant," but literally "the lesser one." From *minōs "less" (see menos) and *-tero-, a comparative suffix (see -tr-).
Portuguese ministro, Catalan ministre, French ministre, Italian ministro, Eastern Vulgar Latin Romanian ministru
Oscan minstreis "of the smaller"
minuto m. (Noun) "minute"
15th cent. Borrowed from Medieval Latin minutum 'id.,' from Latin minutus "small," the passive participle of minuere "to diminish" (see menguar).
mío (Adjective, Pronoun) "(of) mine"
10th cent. Vulgar Latin *mieo. From Latin meum "my," "mine." From Proto-Italic *mejo- 'id.' From Proto-Indo-European *h1mo-i̯o- 'id.' From the root *h1mo- "my."See also mi.
Asturian míu, Portuguesemeu, Galician meu, Catalan meu, French mon, Italian mio, Aromanian njeu, Romanian meu, Sardinian meu
mirar (Verb) "to look (at)"
12th cent. meaning "to admire." First attestation with the sense of "to look" occurs in 13th cent. Occuring in toponyms from at least the 7th cent. (e.g., Miravalles). From Latin mirari "to marvel (at)," from mira "astonishing." From Proto-Italic *smeiro- 'id.' From Proto-Indo-European *sméi̯-ro- "astonishing," but perhaps originally a collective noun meaning laughter. If it indeed meant laughter first, then the root *smei̯- meant "to laugh."
Portuguese mirar, Catalan mirar, French mirer, Italian mirare, Aromanian njir, Romanian mira, Sardinian mirare
Old Church Slavonic smijati sę "smiles," Latvian smiêt "to laugh"
Ancient Greek φιλο-μμειδής (philo-mmeidés) "who likes to laugh"
Sanskrit smáyate "he smiles"
B smiyäṃ "he smiles"