Before I start, I must say that your terminology is quite confusing and plain wrong. You should take your time and read through my answermy answer to this question: Is There a Difference Between Taxonomies and Categories?Is There a Difference Between Taxonomies and Categories?
As I stated before, there is no in_term()
function to check if a post has a specific term. There is however a has_term()
function which accepts the term as first parameter and the taxonomy name as second parameter. So your condition should look like this: (if this is for a specific post type outside the loop)
global $post;
if ( $post->post_type == 'my_post_type' // checks the post type of the post
&& is_single() // Checks if this is a single post
&& has_term( 'term-name or id or slug', 'my_taxonomy', $post->ID ) // Check if post has specific term
) {
// Do something if our condition is true
}