What is another word for "airless"?

Another word for airless depends on context whether you mean lacking air, stuffy, or referring to paint sprayer technology. For airless meaning without air or lacking fresh air, synonyms include breathless, stuffy, stifling, suffocating, close, oppressive, unventilated, and windless. For example, instead of airless room you could say stuffy room or stifling room. Breathless can mean out of breath but also airless in some contexts. For weather meaning no wind, synonyms include windless, calm, still, and becalmed. For example, airless day could be windless day or calm day. For airless paint sprayer meaning without using compressed air, there is no perfect single synonym, but you could say non-pneumatic, air-free, or high-pressure sprayer, as airless sprayers use high pressure pump rather than air compressor. For tires, airless means non-pneumatic. So alternative words include stuffy, stifling, suffocating, breathless, windless, calm, still, close, unventilated, and oppressive. The best synonym depends on whether you mean lacking ventilation, lacking wind, or lacking breath. For general lacking air sense, stuffy and stifling are most common synonyms for airless.