inobservance

noun

in·​ob·​ser·​vance ˌin-əb-ˈzər-vən(t)s 

1

: lack of attention : heedlessness

2

: failure to fulfill : nonobservance

inobservant

ˌin-əb-ˈzər-vənt 

adjective

Word History

Etymology

French & Latin; French, from Latin inobservantia, from in- + observantia observance

First Known Use

1611, in the meaning defined at sense 1