first-class, first-rate, top, the best

(software engineering) class diagram - A type of static structure diagram that describes the structure of a system by showing the system's classes, their attributes, and the relationships between the classes.

(education) class (group of students in a regularly scheduled meeting with a teacher) / class of things (typically products) sharing certain features / (programming, object-oriented programming) class

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

(aviation) economy class

first class (a status, section, etc. of premier rank)

business class

(astronomy) star of the first magnitude; (loosely) brightest star in the sky