1. a spot, stain, mole, freckle MN.i.88; SN.i.170; Vv-a.253; Dhp-a.iv.172 (˚ṃ vā kālakaṃ vā adisvā).
2. a kind of tree Vv.6#7 (= bandhu-jīvaka-puppha-sadisa-pupphā ekā rukkha-jāti).

tila + ka, from its resemblance to a sesame seed