implausible

adj. the antonym of plausible
since plausible means 'seemingly probable', implausible is the exact opposite which is 'dos not seem very probable'

"sorry I have to put down the phone because i need to scratch my nose with both hands" is an implausible excuse

implausible by wrskft June 30, 2007

implacable 

Unable to pacify.
Unable to appease.
Unrelenting.

My enemy is implacable

implacable by Robin December 5, 2004

implausible speculation 

Frivolous musing. Legal term for senseless argument.

The Appeals Court dismissed the defenses argument as implausible speculation.

implausible speculation by mlhiss October 7, 2020

implausible speculation 

Frivolous musing. Legal term for senseless argument.

The Appeals Court dismissed the defenses argument as implausible speculation.

implausible speculation by mlhiss October 7, 2020

implacable 

A descriptive word indicative of a person who is predisposed to very clean teeth.

The guy is so implacable that his dentist had to give up his business.

implacable by Paradoctor April 22, 2018