Inconsiderate, thoughtless. Obsolete. rare.

Not engaged in or characterized by introspection or deliberation.

(un-, prefix1 affix 4.)

Not engaging in or characterized by introspection or deliberation; not reflecting on something.

Not exercising the faculty of thought; thoughtless; unreflecting, undiscriminating.

Not revolving (in various senses).

Not meditative. Also as n. (with the and plural agreement): unmeditative people as a class.

(un-, prefix1 affix 4.)

Unreflecting, unthinking.