The only free and comprehensive online etymological dictionary of the Spanish language
basa f. (Noun) "column"

13th cent. Originally meaning "base." From Latin basa "foundation." For a continued etymology, see base.
base f. (Noun) "base"

Early 18th cent. borrowing from Latin basis 'id.' It replaced the older word basa, now restricted to architecture. Borrowed from Ancient Greek βάσις ‎(básis) "base," but also "step." From Proto-Indo-European *gwh2-ti̯- "gone." From a root *gweh/2- "to go." See also venir.

Italic: Latin venire "to come"

Indo-European: Germanic: Gothic qiman "to come," Old Norse kuma 'id.,' Old Saxon kuman 'id.,' Old High German cuman 'id.,' Old English cuman (English come); Indo-Iranian: Sanskrit gáti "going," Young Avestan jasaiti "to move;" Tocharian: A kum-, B käm-
bastante (Adverb) "enough"

Early 14th cent. From bastar and adverb-forming suffix -ante.

Romance: Western Vulgar Latin: Asturian (dialects) bastante, Portuguese bastante, Galician bastante, Catalan bastant, Italian abbastanza (a bastanza)
bastar (Verb) "to suffice"

13th cent. From Vulgar Latin *bastare "to carry," from Ancient Greek βασάζειν (basázdein) "to lift," "to carry." Ultimately of unknown origin.

Romance: Western Vulgar Latin: Asturian bastar, Portuguese bastar, Galician bastar, Catalan bastar, French baster, Italian bastare

Italic: Latin basterna? "litter to carry a person"
bastardo m. (Noun) "bastard"

14th cent., although an attestation with uncertain meaning as old as early 13th cent. Borrowed from Old French bastard 'id.' From bast "concubinage," of unknown origin, with the pejorative suffix -ard added (for the continued etymology of which, see its cognate suffix -ardo).

"Differing proposals for the root of 'bastard' abound. The notion is posited that a Germanic root *bast 'marriage' is the origin, with the pejorative suffix -ard added to mean it was the child of a 'bad' marriage with a wench of low estate or that a bastard was the peasant offspring of a Christian and a pagan, a conjointure not sanctioned by holy ritual. But that guess reads to me as a conceit no sillier than a paddlesack one." B. Casselman, At the Wording Desk (2016)
basura f. (Noun) "trash," "refuse," "garbage"

12th cent. From Vulgar Latin *vesura, from Latin versura "swept," from verrere "to sweep" (see barrer).

Romance: Western Vulgar Latin: Asturian basura, Aragonese basuera
batalla f. (Noun) "battle"

13th cent. Borrowed from Old Occitan batalha, from Vulgar Latin *batallia 'id.' From Latin battualis "fighting," from battuere "to beat" (see batir).

Also the origin of the surname Batallas, originally given to especially gifted fighters and knights who attempted and achieved an act of heroics on the field of battle.
batir (Verb) "to beat"

12th cent. From Late Latin battere 'id.,' from earlier Latin battuere. Said to be from a Celtic source, probably Gaulish (compare Welsh bathu "beat"). From Proto-Celtic *bat-we/o- 'id.' From Proto-Indo-European *bhed- "to hit."

Ultimately from Proto-Indo-European *bheu̯d- "to strike," from the root *bheu̯- 'id.' See also botar.

Romance: Western Vulgar Latin: Asturian bater, (dialects) batir, Portuguese bater, Galician bater, Catalan batre, French battre, Italian battere; Eastern Vulgar Latin: Aromanian bat, Romanian batter
bebé m. (Noun) "baby"

Borrowed from French bébé 'id.' Of uncertain origin.
beber (Verb) "to drink"

10th cent. From Latin bibere 'id.' From Proto-Italic *pib-e/o- 'id.' From Proto-Indo-European *pi̯-ph3-e/o- 'id.' Imperfective reduplication of *peh3- "to swallow."

Romance: Western Vulgar Latin: Asturian beber, Portuguese beber, Galician beber, Catalan beure, French boire, Italian bere; Eastern Vulgar Latin: Aromanian beau, Romanian bea

Italic: Faliscan pafo "I will drink," Sicel πιβε (pibe) "drink!"

Indo-European: Celtic: Gaulish ibetis, Old Irish ibid, Middle Welsh yuet, Middle Breton euaff, Cornish eva; Balto-Slavic: Old Church Slavonic piti, Russian pit', Czech píti, Slovene píti; Albanian: (Old) pii; Hellenic: Ancient Greek πῑ́νειν (pínein) Armenian: əmpem; Indo-Iranian: Sanskrit píbati

"There are two words for 'drink' [in Proto-Indo-European]. Anatolian retains evidence of *h1ēgwhmi, e.g. Hit ekumi 'I drink', and this is probably the earlier word, found in Italic (Lat ēbrius 'having drunk one's fill, drunk'), Grk nḗphō 'am sober' (ne-h1ēgwhō 'not drink'), and Tocharian (Toch AB yok- 'drink'), which was subsequently replaced (by semantic shift) by *peh3i- 'drink', originally indicating 'swallow'." ~ Mallory & Adams, The Oxford Introduction to Proto-Indo-European and the Proto-Indo-European World (2006)