The term 'T-bone' is a transparent English compound formed in the modern era by directly combining the name of the letter 'T' with the word 'bone'. The 'T' serves a purely descriptive, pictographic function, visually representing the shape of the particular vertebra and its attached processes found in certain cuts of meat. This culinary term, originating in American English, later generated the verbal sense in the mid-20th century, where 'T-bone' metaphorically describes a type of vehicular collision that forms a T-shape, mimicking the structure of the bone. The logic is entirely based on visual analogy, moving from a literal anatomical description to a metaphorical application in mechanics.

Structure: T (shape) + bone (body part) - T: The name of the letter 'T', from Latin via Old English. In this compound, it functions as a descriptive element denoting shape. - bone: From Old English 'bān', of Germanic origin. In this compound, it functions as the core noun indicating the object's material or type.