1. opacification-the process of becoming cloudy or opaque. natural action, natural process, action, activity-a process existing in or produced by nature (rather than by the intent of human beings); the action of natural forces; volcanic activity.Translations.. opacification-the process of becoming cloudy or opaque. natural action, natural process, action, activity-a process existing in or produced by nature (rather than by the intent of human beings); the action of natural forces; volcanic activity. Translations.
A booster is a repeat of a previous vaccine that the dog has already received. The goal of the booster is to boost the dogs immunity up to an effective level. Older dogs need boosters every 1-3 years because otherwise their immunity would start to drop.
Medical Definition of Booster shot. Booster shot: An additional dose of a vaccine needed periodically to 'boost' the immune system. For example, a booster shot of the tetanus and diphtheria (Td) vaccine is recommended for adults every 10 years. Search MedTerms: