'antsier' originates from American English, specifically the word 'antsy', where 'ants' referred to the insect and was used figuratively to suggest agitation.

'antsier' changed from the informal English adjective 'antsy', which itself comes from the phrase 'to have ants in one's pants' (meaning to be restless), and eventually became the colloquial comparative form 'antsier'.

Initially it referred (figuratively) to having 'ants' causing a person to fidget; over time it evolved to mean 'restless or impatient', and 'antsier' now means 'more restless or impatient'.