What rhymes with darkness?

1 syllable:

arc, ark, barch, bark, barke, barque, clark, clarke, darke, harc,hark, harke, karch, lark, larke, marc, mark, marke, marque, merc,narc, parc, park, parke, quark, sark, shark, sparc, spark, starck,stark, starke

2 syllables:

bench mark, blue shark, bull shark, burn mark, call mark, car park,cat shark, charm quark, check mark, cow shark, cub shark, demark,deutsche mark, down quark, embark, embark, fox shark,hash mark, loan shark, nurse shark, premark, remark, remark,sand shark, strange quark, stress mark, stretch mark, top quark,transpark, truth quark, up quark, whale shark, white shark

3 syllables:

accent mark, angel shark, basking shark, beauty quark,bonnet shark, bottom quark, cabbage bark, carbon arc,carpet shark, central park, chatter mark, disembark, ditto mark,dollar mark, easy mark, georgia bark, great blue shark,great white shark, intermark, lemon shark, mako shark,oyster park, ?question-mark, question mark, question-mark,reflex arc, ripple mark, sandbar shark, shoulder mark,thresher shark, tiger shark, trailer park, winter's bark

4 syllables:

amusement park, bonito shark, cassia bark, caustic remark,cinnamon bark, electric arc, letter of marque, letters of marque,mackerel shark, mediamark, minute of arc, national park,quotation mark, requiem shark, strawberry mark,wide of the mark

5 syllables:

cartagena bark, exclamation mark, industrial park, peruvian bark,punctuation mark

6 syllables:

diacritical mark

7 syllables:

gospel according to mark, yellowstone national park

8 syllables:

Yosemite National Park
lark

mark

shark

arc

nark
stark, lark, mark, bark, park, hark. I'm sure there are more but this should get you started.