Synonyms of the word

motiveless

• adj. Without a motive.

unmotivated

• adj. Lacking motivation, without impetus to strive or excel.

unprovoked

• adj. Happening without provocation or motivation.

wanton

• adj. (obsolete) Undisciplined, unruly; not able to be controlled.
• adj. Lewd, immoral; sexually open, unchaste.
• adj. (obsolete) Playful, sportive; being merry or carefree (often used figuratively).
• adj. (obsolete) Self-indulgent, fond of excess; luxurious.
• adj. Capricious, reckless of morality, justice etc.; acting without regard for the law or the well-being of…
• adj. (obsolete) Extravagant, unrestrained; excessive (of speech or thought).
• n. A pampered or coddled person.
• n. An overly playful person; a trifler.
• n. A self-indulgent person, fond of excess.
• n. (archaic) A lewd or immoral person, especially a prostitute.
• v. (intransitive) To rove and ramble without restraint, rule, or limit; to revel; to play loosely; to frolic.
• v. (transitive) To waste or squander, especially in pleasure (often with away).
• v. (intransitive) To act wantonly; to be lewd or lascivious.