n.
Pronunciation: ' in-d ə - ˌ k ā -t ə r
Function: noun
Date: 1666
1 : one that indicates: as a : an index hand (as on a dial) : POINTER b (1) : GAUGE 2B , DIAL 4A (2) : an instrument for automatically making a diagram that indicates the pressure in and volume of the working fluid of an engine throughout the cycle
2 a : a substance (as litmus) used to show visually (as by change of color) the condition of a solution with respect to the presence of a particular material (as a free acid or alkali) b : TRACER 4B
3 : an organism or ecological community so strictly associated with particular environmental conditions that its presence is indicative of the existence of these conditions
4 : any of a group of statistical values (as level of employment) that taken together give an indication of the health of the economy
– in · dic · a · to · ry \ in- ' di-k ə - ˌ to ̇ r- ē \ adjective