lackadaisical

UK: /ˌlækəˈdeɪzɪk^əl/ US: /ˌlækəˈdeɪzɪkəl/ ,(lak′ə dā′zi kəl)

WordReference Random House Learner's Dictionary of American English © 2025

lack•a•dai•si•cal /ˌlækəˈdeɪzɪkəl/   adj. 

1. being without life or spirit;
   listless:
   was lackadaisical about keeping appointments.

lack•a•dai•si•cal•ly, adv. 

WordReference Random House Unabridged Dictionary of American English © 2025

lack•a•dai•si•cal  (lak′ə dā′zi kəl), adj. 

1. without interest, vigor, or determination;
   listless;
   lethargic:
   a lackadaisical attempt.
2. lazy;
   indolent:
   a lackadaisical fellow.

• lackadais(y) (variant of lackaday) + -ical 1760–70

lack′a•dai′si•cal•ly, adv. 
lack′a•dai′si•cal•ness, n. 
Synonyms

• 2. slothful, unambitious, idle.

Collins Concise English Dictionary © HarperCollins Publishers::

lackadaisical / ˌlækəˈdeɪzɪk^əl/ adjective

1. lacking vitality and purpose
2. lazy or idle, esp in a dreamy way

Etymology: 18th Century: from earlier lackadaisy, extended form of lackaday

ˌlackaˈdaisically adverb