commensal
Concise Oxford English Dictionary © 2008 Oxford University Press:
commensal /kəˈmɛns(ə)l/ Biology
▶adjective relating to or denoting an association between two organisms in which one benefits and the other derives neither benefit nor harm. ▶noun a commensal organism, such as many bacteria.
– derivatives
commensalism noun,
commensality /kɒmənˈsalɪti/ noun.
commensalism noun,
commensality /kɒmənˈsalɪti/ noun.
– origin C19: from med. L. commensalis, from com- ‘sharing’ + mensa ‘a table’.
'commensal' also found in these Oxford entries:

