space that is empty of matter

VACUUM
WordClue
DIRTunclean matter
FOAMform of matter
MASSMatter, material
THENThat time<!--is this pronoun?-->
VOIDempty space
CUBBYsmall, confined space
DRIFTthat which moves or is moved
HELIXsmooth space curve
STUFFmatter
SWAMPwetland that is forested
WRONGSomething that is immoral or not good
AFFAIRconcern, matter
BIOLOGYThe study of all life or living matter
SAWDUSTmatter
SUBJECTmatter, topic
SURFINGsport that consists of riding a wave
SUBSTANCEPhysical matter
WRONGDOINGact that is illegal or immoral
CONNOISSEURsubject-matter expert
DECOMPOSITIONbreaking down of living matter
INTERVALspace, season
DIGGERspade