I have had a number of IQ tests: 104, 124, 142, 164, 189. Now some days I have trouble finding my way to work, six miles away. If we ever meet and you need to have a number choose one or just make one up.

Like porn, I know stupid when I see it.

I was tested in my early teens and told my IQ was 143. Got lots of "enrichment" educating, enjoyed it too.
I had a brain-stem stroke from chiropractic manipulation at age 38 (turned 39 in the hospital). Tested IQ dropped to 108. Believe me, a HUGE noticeable difference!!! Just in all areas, math, eading comprehension, understanding/anticipating conversation, general "getting it".
Over the years, most of the intelligence returned, as did my walking, speaking, and other things the stroke took, and wow am I happy about that!
So, not a definition, but bygawd I know it when I see it!

First of all intelligence has to be defined.
Intelligence is not knowledge, you can have a wealth of knowledge and still be completely idiotic in your behavior
Intelligence is not aptitude, savants can be completely incapable in all but one aspect of life in in that display genius levels of aptitude.
Intelligence is not "common sense" or cleverness to terms as equally undefinable as intelligence itself.

Personally I define intelligence as
the high functioning ability of the brain to take in, absorb, retain and combine knowledge for appropriate use at an appropriate time in order to create by application new knowledge without further exterior tuition or guidance.
That is to say problem solving ability

Therefore the only true measure of a person's intelligence is by their success rate in achieving stated objectives.

Eg. The inventor is judged by his inventions that succeed in their intended purpose as to his or her intelligence.
The chef who creates a new taste experience and improves the nutritional value of food is intelligent.
The scientist who combines known mathematics with other seemingly unrelated facts to create an explanation for an as yet unsolved mystery in the natural world by noticing evidential patterns in both for the first time, has performed an act of intelligence.

IQ tests measure ones ability to do well in school, not intelligence. AFAIK intelligence cannot be measured, partly because it cannot be defined.

I've long thought, even when IQ tests were still held in high regard, that it's very difficult to measure intelligence due to it taking many different forms.

I have one friend, for example, who is a doctor of pure mathematics, yet he can't string a basic sentence together; I know several senior software engineers who find it very difficult to carry out basic tasks such as grocery shopping. None of these people, I hasten to add, are on the autistic spectrum, nor are they dyslexic - their brains are simply wired in a particular way. I also know people who performed dismally at school, failed all their exams and work in minimum wage jobs, yet are able to deal with any problems life throws at them and find satisfactory solutions, and I would consider them highly intelligent. Alfred Binet, who with Theodore Simon developed one of the first modern intelligence tests which can be considered a precursor of IQ tests, recognised this: charged with developing a test that would establish whether children were "slow" (the terminology of the time) and would benefit from extra schooling or were "sick" and would be placed in mental asylums, he recognised that in order for such a test to be effective it would need to be qualitative rather than quantitative and tailored to each individual child that sat it.

As the old saying popularly attributed to Einstein says, “Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”

Some people think that problem solving brain power, or knowledge, which can indeed be measured objectively, are measures of intelligence.

But I think that real every day working intelligence, the sort which helps make you a better contributor to the world, is more complex. Involving some emotional qualities at least, such as intellectual honesty, being unwilling to accept second best answers, and unwilling to accept your own interests as a guide to truth, are perhaps even more important. Plus the power of appreciation which helps to set good values. But those things are mainly, though not completely, subjective, and perhaps overall they just mean caring.

Having said which of course it is perhaps an ironic truth that. People who take an interest tend to gain knowledge, and that therefore levels of knowledge are in many ways a measure of how much you care. Which at first glance at least, seems to be against the liberal view that, ignorance is not a failing. But of course that is too simplistic a view, because it is really a failing, not of the ignorant themselves, but of those who educate and do not teach caring as a first principle. Which is a nuance, and in the end caring is all about being prepared to do nuance, and conflict is usually not being prepared to listen to nuance.