1) Inaccessible=it's a proper noun, deriving from single term access=ability to approach, to go, to come in touch. For ex. Access to computer, when one cannot have a computer, usually at the time needed. Or an inaccessible street, passage, path, where one for ex. cannot drive easily//-Have access to one's database, thus for ex. a database in PC may be locked, and access is impossible, then we say that database is inaccessible. It's the opposite of accesible, thus also, something, or some place that is far away, remote. Or for ex. you can't access him easily=you can't approach him/her easily and become friends.

3)Inadequate# adequate, meaning that something is insufficient, not actually enough, or does not meet the relative requirements to achieve something, incompetent with less qualifications for something etc.

In pure Law, we say, inadequate law, due to inadequacy of law chosen from Judge for making decision X, thus law, did/does not contain all rules that cover a decision of a legal case in Court. Or generally, inadequacy of Law, that law X for ex. created and introduced does not cover all possibilities of a certain legal case (either civil or penal one) etc

3)Inadmissible: For ex. plea/lawsuit submitted for Cancellation of decision of Appeal Court to High Court, and this said plea/lawsuit of cancellation, was judged in admissible, thus containing claim(s) that are opposed to Constitution, principles>articles of it, thus punishment cannot be modified, as doc of Trial of cancellation by Appealant to High Court did/does not meet requirements, legal criteria by at least from 51-60% of content of plea for being accepted, actually inadmissible is unacceptable before High Court. Or also Court of State (Συμβούλιο Επικρατείας), whose Judge and Counsellors judge and adjudicate, acts and decisions, administrative acts actually of State may judge a law, or part of it, may judge such decisions of State based on previous laws, (ref. to Positive Law), that are opposed to certain principles and articles deriving from these principles of Constitution. Or opposed to inorganic laws of Constitution, on which organic laws, were later or previously based, and relative laws, on which decisions of Ministries for ex. were issued, as opposed to these (above) criteria of Constitution.

4)Inadvertence=lack of attention, ignorance, negligence, carelessness, relentnesss, to advert is an official term sinonymous to 'warn'.