censer / censor / senser / sensor [ˈsɛn(t)sɜr]
censer – n. – a vessel in which incense is burned, esp. during a religious rite
censor – n. – 1. an official authorized to examine printed matter, films, news, etc., before public release to suppress any parts on the grounds of obscenity, threats to security, etc.; v. tr. – 1. act as an arbitrator of what information the public should receive; 2. make deletions or changes in documents, films, etc., according to social standards or national security
senser – n. – a person that perceives things
sensor – n. – a device giving a signal for the detection or measurement of a physical property to which it responds