lagging

adj

1. falling behind, not keeping up the pace
2. Occurring after; indicating the later phase of

   “A leading wave is one which reaches its maximum value before another, which is thus a lagging wave”

noun

1. (uncountable, usually)The covering of something with strips of felt, wood etc, either as insulation or for protection.
2. (uncountable, usually)The material so used.
3. (countable, slang, usually)A prison sentence, originally one of at least three years.

   “"Whether you'll get a nine or a lagging depends on the answer you give me, Mrs. Inglethorne."”

verb

1. (form-of, gerund, participle, present)present participle and gerund of lag