Secondary school is for pupils aged 11 to 18. This is a standard term without possible confusion.
Further education ("FE") colleges are for pupils aged 16 to 19 and run many courses for adults too. This term is also generally known.
"Technical college" is a term which used to be in common usage as more or less similar to an FE college, and then fell out of use.
Recently, a new type of college called a "technical college" has been established. They are colleges sponsored by universities and / or FE colleges for 14 to 19 year-olds. See https://en.wikipedia.org/wiki/University_Technical_College I am not familiar with them.
In my opinion, in terms of common speech, "technical college" in my view does not have a generally agreed meaning in the UK because of changes in educational terminology over the years.