source of infection

possibility; probability; likelihood

sickness / ill, sick

(slang) abnormal, mentally ill

possible / feasible

possibility, good chance / feasibility

human, person, human being / personality, character / (Buddhism) literally meaning: "human society", referring to one of the six realms of reincarnation in Buddhist cosmology.

(archaic) the world in which people live; the world, society

(dated, rare) a place devoid of people

sex, gender / (grammar) gender