Interesting..... a quick search on the internet produced mo less than a dozen differnet definitions of the word.
Mirriam-Websters defines "cult" as:
cult
Pronunciation: 'k<
Function: noun
Usage: often attributive
Etymology: French & Latin; French culte, from Latin cultus care, adoration, from colere to cultivate —more at WHEEL
Date: 1617
1 : formal religious veneration : WORSHIP
2 : a system of religious beliefs and ritual; also : its body of adherents
3 : a religion regarded as unorthodox or spurious; also : its body of adherents
4 : a system for the cure of disease based on dogma set forth by its promulgator <health cults>
5 a : great devotion to a person, idea, object, movement, or work (as a film or book); especially : such devotion regarded as a literary or intellectual fad b : a usually small group of people characterized by such devotion
The Christian Research instutue says:
There are two ways to define a cult. The first way to describe a cult is popular in the secular media. From this perspective, a cult is a religious or semi-religious sect whose members are controlled almost entirely by a single individual or by an organization.
This kind of cult is usually manipulative, demanding total commitment and loyalty from its followers. Converts are usually cut off from all former associations, including their own families. The Hare Krishnas, the Family of Love led by Moses David Berg, and Sun Myung Moon’s Unification Church are some examples of this kind of a cult.
The second way to define a cult is popular in evangelical Christian circles. From this perspective, a cult is any group that deviates from the orthodox teachings of the historic Christian faith being derived from the Bible and confirmed through the ancient ecumenical creeds.
www.ex-cult.org says:
Of course, the problem with the word 'cult' is that it means different
things to different folks. I'd like to put forward a behavioral definition:
An organization that uses intensive indoctrination techniques to recruit and
maintain members into a totalist ideology.
Intensive indoctrination techniques include:
1) Subjection to stress and fatigue
2) Social disruption, isolation and pressure
3) Self criticism and humiliation
4) Fear, anxiety and paranoia
5) Control of information
6) Escalating commitment
7) Use of auto-hypnosis to induce 'peak' experiences
religioustolerance.org says:
Cult" is a totally meaningless word, because it has so many unrelated definitions. We have identified one positive, four neutral, three negative and one very negative meaning.
In the media, the term is often used to refer to a destructive religious group which: Is new, small, evil, and dangerous.
Often has a single charismatic leader.
Engages in brainwashing and other mind control techniques.
Believes that the end of the world is imminent.
Collects weapons in preparation for attack.
The word has other neutral or positive meanings, such as: A Christian group that teaches one or more untraditional beliefs.
Any group which forms a small minority in a given country.
A style of worship.
and
Cult: From the Latin word "cultus" -- meaning worship. Cult is a word with many religious meanings (and some secular as well) which should be used with great care to avoid misunderstanding. We recommend the neutral term "new religious movement" be used in its place. Even better is to refer to a religious group by its name:
Traditional theological usage: a style of worship and its associated rituals. It can be applied to any faith group.
Sociological usage: a small religious group that exists in a state of tension with the predominant religion; e.g. Christianity in Pakistan.
General religious usage: a small, recently created religious group; not a variant of an established religion. Often headed by a single charismatic leader.
Evangelical usage: a religious group that considers themselves to be Christian but which denies one or more historical beliefs of Protestant Christianity.
Counter-cult movement usage: Same as Evangelical usage.
Anti-cult movement usage: a small, evil religious group, often with a single charismatic leader, who engage in deceptive recruiting, brainwashing and other mind control techniques
Popular belief: A doomsday, dangerous, destructive religious movement whose members risk their life to belong.
Certainly, it is next to impossible to "clearly and completely" define the word cult. Using the scope of definitions above, almost any group of people can be described as a cult.

That said, here is a page written by a mason that defends against freemasonry being a destructive cult.
Masonry a cult? It is worth a look.
peace-Lauren