'asthmatic-sounding' is a modern English compound formed by combining the adjective 'asthmatic' (from 'asthma') and the present participle 'sounding' from the verb 'sound'. 'asthmatic' originates from Greek, specifically the word 'asthma', where the root meant 'panting'. 'sound' (noun/verb) traces back to Latin 'sonus' via Old French 'son'.

'asthma' entered English via Latin 'asthma' (and Old French/Medieval Latin forms); the adjective 'asthmatic' developed in English to describe someone affected by asthma. Separately, the verb/noun 'sound' (Latin 'sonus' -> Old French 'son' -> Middle English 'soun/sound') produced the participle 'sounding'. These elements were later combined in modern English to form the descriptive compound 'asthmatic-sounding'.

Initially 'asthma' meant 'panting' or 'shortness of breath'; over time 'asthmatic' described the medical condition or someone suffering from it. The compound 'asthmatic-sounding' evolved to mean 'resembling the sound typical of asthma' (i.e., wheezy or breathy).