There is no consensus on the status of a word as a phrase.

Traditional grammar used to say that a phrase is two or more words; however, The Cambridge Grammar of the English Language, a "modern traditional" grammar, uses one-word phrases. On the other hand, transformational grammar used to say that a phrase is one or more words; however, its contemporary update no longer does so (because it does not allow unary branching).

The Wikipedia article on noun phrases summarises it nicely:

Status of single words as phrases

Traditionally, a phrase is understood to contain two or more words. The traditional progression in the size of syntactic units is word < phrase < clause, and in this approach a single word (such as a noun or pronoun) would not be referred to as a phrase. However, many modern schools of syntax – especially those that have been influenced by X-bar theory – make no such restriction.[3] Here many single words are judged to be phrases based on a desire for theory-internal consistency. A phrase is deemed to be a word or a combination of words that appears in a set syntactic position, for instance in subject position or object position.

Those who define a phrase as one or more words do so for theory-internal consistency reasons. As an English learner, I don't think anyone should fault you for using "phrase" to mean two or more words.

There is no consensus on the status of a word as a phrase.

Traditional grammar used to say that a phrase is two or more words; however, The Cambridge Grammar of the English Language, a "modern traditional" grammar, uses one-word phrases. On the other hand, transformational grammar used to say that a phrase is one or more words; however, its contemporary update no longer does so (because it does not allow unary branching).

The Wikipedia article on noun phrases summarises it nicely:

Status of single words as phrases

Traditionally, a phrase is understood to contain two or more words. The traditional progression in the size of syntactic units is word < phrase < clause, and in this approach a single word (such as a noun or pronoun) would not be referred to as a phrase. However, many modern schools of syntax – especially those that have been influenced by X-bar theory – make no such restriction.[3] Here many single words are judged to be phrases based on a desire for theory-internal consistency. A phrase is deemed to be a word or a combination of words that appears in a set syntactic position, for instance in subject position or object position.

Those who define a phrase as one or more words do so for theory-internal consistency reasons. As an English learner, I don't think anyone should fault you for using "phrase" to mean two or more words.

Edit: It seems that even traditional grammar in the second half of last century was open to the idea of a phrase being one word. Here's Quirk et al's well-known "A Comprehensive Grammar of the English Language (1985)" (p. 42):

The grammatical hierarchy

clauses, which consist of one or more
phrases, which consist of one or more
words, which consist of one or more
morphemes.

There is no consensus on the status of a word as a phrase.

Traditional grammar used to say that a phrase is two or more words; however, The Cambridge Grammar of the English Language, a "modern traditional" grammar, uses one-word phrases. On the other hand, transformational grammar used to say that a phrase is one or more words; however, it's contemporary update no longer does so (because it does not allow unary branching).

The Wikipedia article on noun phrases summarises it nicely:

Status of single words as phrases

Traditionally, a phrase is understood to contain two or more words. The traditional progression in the size of syntactic units is word < phrase < clause, and in this approach a single word (such as a noun or pronoun) would not be referred to as a phrase. However, many modern schools of syntax – especially those that have been influenced by X-bar theory – make no such restriction.[3] Here many single words are judged to be phrases based on a desire for theory-internal consistency. A phrase is deemed to be a word or a combination of words that appears in a set syntactic position, for instance in subject position or object position.

Those who define a phrase as one or more words do so for theory-internal consistency reasons. As an English learner, I don't think anyone should fault you for using "phrase" to mean two or more words.

There is no consensus on the status of a word as a phrase.

Traditional grammar used to say that a phrase is two or more words; however, The Cambridge Grammar of the English Language, a "modern traditional" grammar, uses one-word phrases. On the other hand, transformational grammar used to say that a phrase is one or more words; however, its contemporary update no longer does so (because it does not allow unary branching).

The Wikipedia article on noun phrases summarises it nicely:

Status of single words as phrases

Traditionally, a phrase is understood to contain two or more words. The traditional progression in the size of syntactic units is word < phrase < clause, and in this approach a single word (such as a noun or pronoun) would not be referred to as a phrase. However, many modern schools of syntax – especially those that have been influenced by X-bar theory – make no such restriction.[3] Here many single words are judged to be phrases based on a desire for theory-internal consistency. A phrase is deemed to be a word or a combination of words that appears in a set syntactic position, for instance in subject position or object position.

Those who define a phrase as one or more words do so for theory-internal consistency reasons. As an English learner, I don't think anyone should fault you for using "phrase" to mean two or more words.