helmet vs plum

helmet

noun
  • A contemptible or stupid person. 

  • The hood-shaped upper sepal or petal of some flowers, as of the monkshood or the snapdragon. 

  • A naked shield or protuberance on the top or fore part of the head of a bird. 

  • The feature above a shield on a coat of arms. 

  • The glans penis. 

  • A hard, protective head covering, typically part of armour. 

  • The upper part of a chemist's retort. 

verb
  • To cover with, or as if with, a helmet. 

plum

noun
  • A fool, an idiot. 

  • A stone-fruit tree which bears this fruit, Prunus domestica. 

  • Prunus americana (American plum) 

  • Prunus sect. Armeniaca (better known as apricots) 

  • Prunus rivularis (creek plum or hog plum) 

  • A desirable or choice thing of its kind; a prize selection; a choice appointment, assignment etc. 

  • Prunus mume, an Asian fruit more closely related to the apricot than the plum, usually consumed pickled, dried, or as a juice or wine; ume. 

  • A dark bluish-red color/colour, the colour of some plums. 

  • An edible, fleshy stone fruit of Prunus domestica (European plum), often of a dark red or purple colour. 

  • Prunus ursina (bear's plum) 

  • Prunus angustifolia (Chickasaw plum or sand plum) 

  • Prunus hortulana (hortulan plum) 

  • Prunus nigra (Canadian plum or black plum) 

  • Prunus spinosa (sloe) 

  • Prunus subcordata (Klamath plum or Oregon plum) 

  • Prunus salicina (Chinese plum or Japanese plum) 

  • Prunus cerasifera (cherry plum or myrobalan) 

  • A testicle. 

adv
  • Completely; utterly. 

verb
  • To plumb. 

adj
  • Of a dark bluish-red colour. 

  • Choice; especially lavish or preferred. 

  • Plumb 

How often have the words helmet and plum occurred in a corpus of books? (source: Google Ngram Viewer )