Muggy \Mug"gy\ (m[u^]g"g[y^]), a. [Compar. {Muggier}
(m[u^]g"g[i^]*[~e]r); superl. {Muggiest}.] [Cf. Icel. mugga
mist, mugginess. Cf. 4th {Mold}.]
1. Moist; damp; moldy; as, muggy straw.
[1913 Webster]
2. Warm, damp, and windless; uncomfortably hot and humid;
sultry; as, muggy air, weather.
[1913 Webster]