Pronunciation: [bɹˌɒnkɪˈə͡ʊlə] (IPA) 
The word "bronchiolar" is spelled with the letter combination "ch" but pronounced with a sound similar to "k". This is because the "ch" sound in this word is actually an example of the "voiceless velar fricative" sound (/x/ in IPA phonetic transcription). This sound is made by forcing air through the narrow space between the back of the tongue and the velum, which is the soft tissue at the back of the roof of the mouth.
Bronchiolar refers to anything related to the bronchioles, which are the smallest airways in the lungs. In the human respiratory system, the bronchioles are branches that arise from the bronchi and further divide into even smaller tubes called terminal bronchioles. These bronchioles play a crucial role in the respiratory process by conducting the inhaled air to the alveoli, where gas exchange occurs between the air and the bloodstream.
In a more specific sense, the term bronchiolar can be used to describe the anatomical structure or the physiological function associated with the bronchioles. Anatomically, bronchiolar refers to the thin-walled, branching tubes that lack cartilage and gradually decrease in diameter as they extend deeper into the lung tissue. These bronchiolar structures are lined with specialized cells, including ciliated epithelial cells and Clara cells, which function to remove particles and secrete protective substances, respectively.
From the physiological perspective, bronchiolar pertains to the processes or functions that occur within or are attributed to the bronchioles. This can include bronchoconstriction (narrowing of the airways) or bronchodilation (relaxation and widening of the airways), which are regulated by the smooth muscle cells present in the bronchiolar walls. Additionally, bronchiolar functions encompass the control of airflow resistance, the regulation of mucus secretion, and the redistribution of air within the lungs.
The word "bronchiolar" is derived from the combination of two roots: "bronchi" and "-olar".
The root "bronchi" comes from the Greek word "bronkhos", meaning "windpipe" or "breath". It refers to the branching air passages in the respiratory system that extend from the trachea into the lungs, responsible for carrying air to the alveoli.
The suffix "-olar" is a combining form borrowed from the Latin language, where it indicates "pertaining to" or "relating to". It is derived from the Latin noun "ulus" meaning "small" or "little".
Therefore, the etymology of "bronchiolar" suggests that it describes something that pertains to or is related to the small air passages known as bronchioles in the respiratory system.
