WordNet sense 1 (hot or warm and humid):

muggy, steamy

WordNet sense 2 (covered or soaked with a liquid such as water):

wet

WordNet sense 3 (hard to deal with; especially causing pain or embarrassment):

awkward, embarrassing, unenviable

WordNet sense 4 (not easy; requiring great physical or mental effort to accomplish or comprehend or endure):

difficult, hard

WordNet sense 5 (having the sticky properties of an adhesive):

gluey, glutinous, gummy, mucilaginous, pasty, viscid, viscous, pasty

WordNet sense 6 (tending to adhere):

adhesive