Definition

1. Noun:

   • A submersible warship, especially a submarine: A naval vessel capable of operating underwater, typically armed with torpedoes.
   • A large sandwich: A long sandwich made by filling a lengthwise-split roll with various meats, cheeses, and other ingredients like lettuce, tomato, and condiments. Regional names vary.

2. Verb:

   • To act as a substitute; to replace: To take the place or perform the function of another person or thing, often temporarily.

Usage Examples

• Noun (Submersible):

  • The navy deployed a sub to patrol the coastal waters.
  • Sonar detected an enemy sub in the area.

• Noun (Sandwich):

  • I ordered an Italian sub with ham, salami, and provolone.
  • For lunch, she often gets a veggie sub from the deli.

• Verb:

  • Can you sub for me at the meeting tomorrow?
  • He had to sub as the team's goalie when the starter was injured.

Advanced Usage

• "To sub in": To enter a game or situation as a substitute.
  • The coach told the rookie to sub in for the tired midfielder.
• "To sub out": To leave a game or situation and be replaced by a substitute.
  • The star player subbed out in the final minutes to rest.

Variants and Related Words

• Substitute (n/v): A person or thing acting in place of another; to act as a replacement. (This is the full, more formal version of "sub").
• Submarine (n): The full term for a submersible warship or a type of sandwich (synonymous with "sub" in both contexts).
• Subbing (gerund/n): The action of working as a substitute.
  • She does a lot of subbing at the local high school.

Synonyms

• Noun (Warship): Submarine, U-boat.
• Noun (Sandwich): Hoagie, hero, grinder, po'boy (regional variations).
• Verb: Replace, stand in, fill in, cover.

Related Phrasal Verbs

• Sub for: To substitute for someone or something.
  • I need someone to sub for the receptionist next week.
• Sub in: (See Advanced Usage above).
• Sub out: (See Advanced Usage above).

Related Idioms

• Sub par: Below average or expected standard. (Note: This idiom uses "sub" as a prefix meaning "under," not directly from the standalone word "sub").
  • His performance was sub par today.

Noun

1. a submersible warship usually armed with torpedoes
2. a large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States

Verb

1. be a substitute
   • The young teacher had to substitute for the sick colleague
   • The skim milk substitutes for cream--we are on a strict diet